Add support for coderabbit summary in PR description

[miroslavpojer]

Background

The coderabbit GH app can provide a summary of the PR description.
The Release Notes generator should support it as an alternative source of Release Notes.

Feature

• Add logic to use this summary a a source of Release Notes.
• Add ignore input for this option to define which summary chapters should be ignored.
• Add the order of mining:
  • 1st look for Release Notes regex
  • 2nd (if not detection in 1st try) look for another regex (default set for coderabbitai)
    • if 2nd not detection in 2nd try, act like no Release Notes present