feat: support prometheus configuration in agent

[yuvraj-singh-3]

Description

Git issue: #153

Add support for custom prometheus scrape_configs in sysdig-agent configmap. Ref: https://prometheus.io/docs/prometheus/latest/configuration/configuration/#configuration-file

This is supported in agent's configmap and then configured in values.yaml

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[ocofaigh]

Please give me some time to try this out. I'll have to push some extra updates to this PR:

• address failing pre-commit hooks
• expose in the DA (which will need a supporting markdown doc for the complex input)
• update one of the tests to test this feature

[ocofaigh]

Covered in #167