Bump mypy from 0.982 to 1.4.0

Bumps [mypy](https://github.com/python/mypy) from 0.982 to 1.4.0.
- [Commits](python/mypy@v0.982...v1.4.0)

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

Signed-off-by: dependabot[bot] <support@github.com>

requirements-mypy.txt

@@ -1,6 +1,6 @@
 typing
 # Mypy requires typed-ast, which is broken on PyPy 3.7 (could work in PyPy 3.8).
-mypy==0.982; implementation_name == "cpython"
+mypy==1.4.0; implementation_name == "cpython"
 types-simplejson
 types-certifi
 types-requests