feat: Save postgres superuser password in secretstore

[lindseysimple]

Resolves #5050. Save postgres superuser password in secretstore.

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• I am not introducing a breaking change (if you are, flag in conventional commit message with BREAKING CHANGE: describing the break)
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[codecov-commenter]

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Codecov Report

Attention: Patch coverage is 9.09091% with 50 lines in your changes missing coverage. Please review.

Project coverage is 28.04%. Comparing base (abfbcc6) to head (77b7903).

Files with missing lines	Patch %	Lines
...ecurity/bootstrapper/postgres/handlers/handlers.go	0.00%	30 Missing ⚠️
internal/security/secretstore/init.go	0.00%	19 Missing ⚠️
...ternal/security/bootstrapper/postgres/configure.go	0.00%	1 Missing ⚠️

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Additional details and impacted files

@@            Coverage Diff             @@
##             main    #5051      +/-   ##
==========================================
- Coverage   28.10%   28.04%   -0.06%     
==========================================
  Files         256      256              
  Lines       18460    18515      +55     
==========================================
+ Hits         5188     5193       +5     
- Misses      12074    12124      +50     
  Partials     1198     1198              

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[cloudxxx8]

Suggested change

	postgresSecretName = "postgres" // nolint:gosec
	postgresSecretName = "postgres"