[Security] fix DBAL connection typehint
bug #10723 [Security] fix DBAL connection typehint (Tobion)

This PR was merged into the 2.3 branch.

Discussion
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[Security] fix DBAL connection typehint

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | -
| License       | MIT

Commits
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c05edcc [Security] fix DBAL connection typehint