fix: mark database drivers as optional peer dependencies

[DRoet]

Pull Request check-list

Please make sure to review and check all of these items:

• Does npm run test or npm run test-DIALECT pass with this change (including linting)?
• Does the description below contain a link to an existing issue (Closes #[issue]) or a description of the issue you are solving?
• Have you added new tests to prevent regressions?
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• Did you update the typescript typings accordingly (if applicable)?
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Description of change

same as #12484 but for the master branch

[codecov]

Codecov Report

Merging #12494 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master   #12494   +/-   ##
=======================================
  Coverage   96.38%   96.38%           
=======================================
  Files          95       95           
  Lines        9257     9257           
  Branches       61       61           
=======================================
  Hits         8922     8922           
  Misses        322      322           
  Partials       13       13           

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