Automate labeling PRs as community sourced

[emmyoop]

resolves https://dbtlabs.atlassian.net/browse/OSS-3

Problem

GitHub doesn't have an easy way to filter out PRs that are created by the core/adapters team when tracking community PRs.

Solution

Add a special "community" label to PRs opened in non-draft or converted from draft to ready for review when the author is not on the core or adapters team

Checklist

• I have read the contributing guide and understand what's expected of me
• I have run this code in development and it appears to resolve the stated issue
• This PR includes tests, or tests are not required/relevant for this PR
• This PR has no interface changes (e.g. macros, cli, logs, json artifacts, config files, adapter interface, etc) or this PR has already received feedback and approval from Product or DX
• This PR includes type annotations for new and modified functions

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 88.04%. Comparing base (c6c0c79) to head (fce7263).

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #9797      +/-   ##
==========================================
- Coverage   88.09%   88.04%   -0.05%     
==========================================
  Files         178      178              
  Lines       22461    22461              
==========================================
- Hits        19787    19776      -11     
- Misses       2674     2685      +11     

Flag	Coverage Δ
integration	85.42% <ø> (-0.13%)	⬇️
unit	61.73% <ø> (ø)

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[ChenyuLInx]

Does other people use the label-community.yml? should we consider moving it to core repo?
The patch it self looks great!

[emmyoop]

@ChenyuLInx The meat of the logic already lives in dbt-labs/actions. The idea is adapters will also use it. However each repo needs to have their own copy like this one for permission purposes to be able to label the PRs and trigger at the right time.