Changelog parser checks for links and ensures they are in markdown syntax

[izgeri]

Is your feature request related to a problem? Please describe.

We have automated processes (eg the Conjur OSS suite) that consume the change logs. This change log parser tool has already done a lot to standardize the change log format that we use, but sometimes change logs include links in the format #123 that our automation can't parse. Including the same text in our release notes output doesn't resolve the link. In addition, sometimes entries don't include links at all, but we'd like to always reference the issue related to a change.

Describe the solution you would like

We're asking that all change logs add links to each entry, and that the links are in markdown format (e.g. [link text](link url), or [cyberark/repo#123](https://github.com/cyberark/repo/issues/123)).

All suite repos already have the changelog parser running at the start of their pipelines to alert early about any errors. We'd like to have the parser:

• Note when there are apparent links (terms of the form #123, or references to files that end in .md) that are not in markdown format. The parser should fail with a clear error if it detects instances of a malformed link on change log entry.
• Note when there are change log entries that do not include a link, factoring in that entries can span multiple consecutive lines but should belong to the same markdown bullet. The parser should fail with a clear error if it detects a change log entry without a link.

Describe alternatives you have considered

The only real alternative is manually enforcing this pattern, but it would be most consistently applied if we can automate validation that we're following this standard.

Additional context

Some repos have LONG historical change logs that don't apply this standard. As part of making this change, we may need to:

• Apply the link requirement only to changelog entries for versions that are after a certain release date (not sure if this is possible)
• Update some recent change log entries to include proper markdown links