minor symfony#38070 [Validator] Add Bosnian (BS) translation (tambait)

This PR was merged into the 3.4 branch.

Discussion
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[Validator] Add Bosnian (BS) translation

| Q             | A
| ------------- | ---
| Branch?       | 3.4
| Bug fix?      | no
| New feature?  | no
| Deprecations? | no
| Tickets       | Fix symfony#30275
| License       | MIT
| Doc PR        | none

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Commits
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dd44563 add bosnian (bs) translation

Author: fabpot