[changelog] Support multiple matchers for labels

[netomi]

Right now, a single matcher is supported for items like the title or the body like explained in the documentation:

labelers:
          # The label to be applied.
          # 
        - label: 'issue'

          # Matches the text of the first commit line.
          # Value may be plain text or regex.
          # Use `regex:` as prefix to indicate a regex.
          # 
          title: 'regex:fix:'

          # Matches the full text of the commit.
          # Value may be plain text or regex.
          # Use `regex:` as prefix to indicate a regex.
          # 
          body: 'Fixes #'

it would be quite handy to additionally support a list of matchers like that:

  - label: 'dependencies'
    title:
      - 'regex:deps:i'
      - 'regex:dependencies:i'
      - 'regex:bump:i'

where if any of the matchers matches, the label will be applied. Additionally, support adding a flag after the second colon to be able to express insensitive pattern. This would be similar to the javascript notation of e.g. '/bump:/i'.

The notation for the flag might not work in a backwards compatible way, but having the possibility to express case-insensitive pattern in an easy way would be certainly useful imho.

[aalmiray]

As a workaround you could use regex:deps|dependencies|bump.
Migrating the title property from scalar to list/array is a non-compatible change which should be made in v2 IMHO.

[netomi]

ty for providing the workaround, that certainly helps.

Also I realized you can specify flags in a java regexp pattern like that in the regexp itself:

(?idmsuxU-idmsuxU) - Nothing, but turns match flags i d m s u x U on - off