Fix broken xrefs with fragments

[btat]

PR #19 adds the springio/antora-xref-extension, which surfaces some broken links that need to be fixed before it can be merged.

The logs from this CI run provides a list of the broken links.

[btat]

Current broken xrefs blocking #19

[01:00:30.389] ERROR (asciidoctor): target fragment of xref not found: ./architecture.adoc#_server-charts
    file: /home/runner/work/rke2-product-docs/rke2-product-docs/versions/latest/modules/en/pages/advanced.adoc
    source: /home/runner/work/rke2-product-docs/rke2-product-docs (branch: HEAD <worktree> | start path: versions/latest)
[01:00:30.926] ERROR (asciidoctor): target fragment of xref not found: install/configuration.adoc#_configuration-file
    file: /home/runner/work/rke2-product-docs/rke2-product-docs/versions/latest/modules/en/pages/install/quickstart.adoc
    source: /home/runner/work/rke2-product-docs/rke2-product-docs (branch: HEAD <worktree> | start path: versions/latest)
[01:00:30.927] ERROR (asciidoctor): target fragment of xref not found: install/configuration.adoc#_configuration-file
    file: /home/runner/work/rke2-product-docs/rke2-product-docs/versions/latest/modules/en/pages/install/quickstart.adoc
    source: /home/runner/work/rke2-product-docs/rke2-product-docs (branch: HEAD <worktree> | start path: versions/latest)
[01:00:31.094] WARN (asciidoctor): Parse error when validating xrefs (node.getLogger is not a function)
    file: /home/runner/work/rke2-product-docs/rke2-product-docs/versions/latest/modules/en/pages/networking/basic_network_options.adoc
    source: /home/runner/work/rke2-product-docs/rke2-product-docs (branch: HEAD <worktree> | start path: versions/latest)
[01:00:33.687] ERROR (asciidoctor): target fragment of xref not found: install/ha.adoc#_3_launch_additional_server_nodes
    file: /home/runner/work/rke2-product-docs/rke2-product-docs/versions/latest/modules/zh/pages/datastore/backup_restore.adoc
    source: /home/runner/work/rke2-product-docs/rke2-product-docs (branch: HEAD <worktree> | start path: versions/latest)
[01:00:33.735] ERROR (asciidoctor): target fragment of xref not found: advanced.adoc#_node_labels_and_taints
    file: /home/runner/work/rke2-product-docs/rke2-product-docs/versions/latest/modules/zh/pages/datastore/external.adoc
    source: /home/runner/work/rke2-product-docs/rke2-product-docs (branch: HEAD <worktree> | start path: versions/latest)
[01:00:33.781] ERROR (asciidoctor): target fragment of xref not found: ./quickstart.adoc#_2_enable_the_rke2_server_service
    file: /home/runner/work/rke2-product-docs/rke2-product-docs/versions/latest/modules/zh/pages/install/airgap.adoc
    source: /home/runner/work/rke2-product-docs/rke2-product-docs (branch: HEAD <worktree> | start path: versions/latest)
[01:00:33.998] ERROR (asciidoctor): target fragment of xref not found: ./configuration.adoc#_configuration_file
    file: /home/runner/work/rke2-product-docs/rke2-product-docs/versions/latest/modules/zh/pages/install/windows_airgap.adoc
    source: /home/runner/work/rke2-product-docs/rke2-product-docs (branch: HEAD <worktree> | start path: versions/latest)
[01:00:34.026] WARN (asciidoctor): Parse error when validating xrefs (node.getLogger is not a function)
    file: /home/runner/work/rke2-product-docs/rke2-product-docs/versions/latest/modules/zh/pages/networking/basic_network_options.adoc
    source: /home/runner/work/rke2-product-docs/rke2-product-docs (branch: HEAD <worktree> | start path: versions/latest)
[01:00:34.050] ERROR (asciidoctor): target fragment of xref not found: add-ons/helm.adoc#_customizing_packaged_components_with_helmchartconfig
    file: /home/runner/work/rke2-product-docs/rke2-product-docs/versions/latest/modules/zh/pages/networking/multus_sriov.adoc
    source: /home/runner/work/rke2-product-docs/rke2-product-docs (branch: HEAD <worktree> | start path: versions/latest)
[01:00:34.050] ERROR (asciidoctor): target fragment of xref not found: add-ons/helm.adoc#_customizing_packaged_components_with_helmchartconfig
    file: /home/runner/work/rke2-product-docs/rke2-product-docs/versions/latest/modules/zh/pages/networking/multus_sriov.adoc
    source: /home/runner/work/rke2-product-docs/rke2-product-docs (branch: HEAD <worktree> | start path: versions/latest)
[01:00:34.062] ERROR (asciidoctor): target fragment of xref not found: add-ons/helm.adoc#_customizing-packaged-components-with-helmchartconfig
    file: /home/runner/work/rke2-product-docs/rke2-product-docs/versions/latest/modules/zh/pages/networking/networking_services.adoc
    source: /home/runner/work/rke2-product-docs/rke2-product-docs (branch: HEAD <worktree> | start path: versions/latest)
[01:00:34.062] ERROR (asciidoctor): target fragment of xref not found: add-ons/helm.adoc#_customizing_packaged_components_with_helmchartconfig
    file: /home/runner/work/rke2-product-docs/rke2-product-docs/versions/latest/modules/zh/pages/networking/networking_services.adoc
    source: /home/runner/work/rke2-product-docs/rke2-product-docs (branch: HEAD <worktree> | start path: versions/latest)
[01:00:34.063] ERROR (asciidoctor): target fragment of xref not found: add-ons/helm.adoc#_customizing_packaged_components_with_helmchartconfig
    file: /home/runner/work/rke2-product-docs/rke2-product-docs/versions/latest/modules/zh/pages/networking/networking_services.adoc
    source: /home/runner/work/rke2-product-docs/rke2-product-docs (branch: HEAD <worktree> | start path: versions/latest)
[01:00:34.124] ERROR (asciidoctor): target fragment of xref not found: ../install/configuration.adoc#配置文件
    file: /home/runner/work/rke2-product-docs/rke2-product-docs/versions/latest/modules/zh/pages/reference/linux_agent_config.adoc
    source: /home/runner/work/rke2-product-docs/rke2-product-docs (branch: HEAD <worktree> | start path: versions/latest)
[01:00:36.163] ERROR (asciidoctor): target fragment of xref not found: security/pod_security_standards.adoc#_pod_security_standards
    file: /home/runner/work/rke2-product-docs/rke2-product-docs/versions/latest/modules/zh/pages/security/hardening_guide.adoc
    source: /home/runner/work/rke2-product-docs/rke2-product-docs (branch: HEAD <worktree> | start path: versions/latest)