feat: respect sqlfluff configuration file

[reata]

Closes #548

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 99.50%. Comparing base (3574f2d) to head (950b510).
Report is 3 commits behind head on master.

❗ Current head 950b510 differs from pull request most recent head 54114c9. Consider uploading reports for the commit 54114c9 to get more accurate results

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #582   +/-   ##
=======================================
  Coverage   99.50%   99.50%           
=======================================
  Files          41       41           
  Lines        2219     2219           
=======================================
  Hits         2208     2208           
  Misses         11       11           

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[reata]

Two windows-related issues to be solved:

1. working path in C driver, repo path in D driver. sqlfluff throws an exception when no common path can be extracted. This is fixed in latest sqlfluff main branch via b7f6933ac52bea7f12189a54458eb0229788d107.
2. os.path.expanduser("~") in windows-latest image does not expand and instead returns "~".