Allow square brackets [ and ] in BasicPostgresSecurityValidator

[suddendust]

Description

This PR allows [ and ] in BasicPostgresSecurityValidator.

Testing

Added UTs.

Checklist:

• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• Any dependent changes have been merged and published in downstream modules

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 80.40%. Comparing base (bf7e428) to head (000f0de).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff            @@
##               main     #254   +/-   ##
=========================================
  Coverage     80.40%   80.40%           
  Complexity     1256     1256           
=========================================
  Files           227      227           
  Lines          5839     5839           
  Branches        517      517           
=========================================
  Hits           4695     4695           
  Misses          790      790           
  Partials        354      354           

Flag	Coverage Δ
integration	80.40% <ø> (ø)
unit	57.68% <ø> (ø)

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