match section names containing prefix character (normally [)

[tja523]

Currently sections with names including the prefix (normally [) can be
created by this provider, but they are then not matched by the regex,
meaning puppet will create a new section (with the same name) every time
it runs. Fix that by allowing the section prefix in the section name.
Any line that starts with the correct prefix (normally [) and ends with
the correct suffix (normally ]) is treated as a valid section header,
regardless of what is between them.

This is needed for splunk inputs.conf file where regexes, including
square brackets, are allowed inside the section name.

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[daianamezdrea]

Hi @tja523, just closing and reopening the PR to trigger the tests

[github-actions]

This PR has been marked as stale because it has been open for a while and has had no recent activity. If this PR is still important to you please drop a comment below and we will add this to our backlog to complete. Otherwise, it will be closed in 7 days.

[tja523]

Hi, yes this PR is still important to us, so please reopen it.

[LukasAud]

Hi @tja523, we will be reopening your PR soon. We are currently using the stale-bot to help organise our work better, sorry if this caused any inconvenience. Hopefully, we will be able to take a closer look and properly review your PR soon.

[chelnak]

@tja523 This looks good to me. Thank you.