ssh-key-action 2.8.0 released

Others

• Update to Node.js v24
• add support: windows-2025, macos-14, macos-15, and ubuntu-24.04
• drop support: windows-2019, macos-11, macos-12, and ubuntu-20.04
• add container support: alpine:3.21 - alpine:3.23, centos:stream10, and ubuntu:24.04
• drop container support: alpine:3.10 - alpine:3.13, centos:stream8, and ubuntu:20.04
• Add workaround; "HOME is not defined" (refer to: issue #184)