fix: relax Bun version check in Nix pre-push

[harukz]

Issue for this PR

Closes #47332

Type of change

• Bug fix
• New feature
• Refactor / code improvement
• Documentation

What does this PR do?

Allows the pre-push hook to continue with a warning when the Bun version mismatch occurs inside a Nix shell.

The Nix dev shell currently provides Bun 1.3.13 while the repository requires Bun 1.3.14. Bun 1.3.13 can still complete the pre-push typecheck successfully, so the version mismatch should not block pushes from the Nix development environment.

This is consistent with the existing Nix package behavior in #33166.

How did you verify your code works?

Inside nix develop with Bun 1.3.13:

> bun --version
1.3.13
> ./.husky/pre-push
Warning: This script requires bun@^1.3.14, but you are using bun@1.3.13
...
Tasks:    30 successful, 30 total

Confirmed that the same mismatch still fails outside a Nix shell:

env -u IN_NIX_SHELL ./.husky/pre-push
> error: This script requires bun@^1.3.14, but you are using bun@1.3.13

Also confirmed that git push succeeds from the Nix development shell.

Screenshots / recordings

N/A

Checklist

• I have tested my changes locally
• I have not included unrelated changes in this PR