Bump mypy from 1.4.1 to 1.5.1 in /htmxdj

Bumps [mypy](https://github.com/python/mypy) from 1.4.1 to 1.5.1.
- [Commits](python/mypy@v1.4.1...v1.5.1)

---
updated-dependencies:
- dependency-name: mypy
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>

htmxdj/requirements/local.txt

@@ -6,7 +6,7 @@ psycopg[binary]==3.1.9  # https://github.com/psycopg/psycopg
 
 # Testing
 # ------------------------------------------------------------------------------
-mypy==1.4.1  # https://github.com/python/mypy
+mypy==1.5.1  # https://github.com/python/mypy
 django-stubs[compatible-mypy]==4.2.4  # https://github.com/typeddjango/django-stubs
 pytest==7.4.2  # https://github.com/pytest-dev/pytest
 pytest-sugar==0.9.7  # https://github.com/Frozenball/pytest-sugar