Bump mypy from 0.782 to 0.790 (#4723)

* Bump mypy from 0.782 to 0.790

Bumps [mypy](https://github.com/python/mypy) from 0.782 to 0.790.
- [Release notes](https://github.com/python/mypy/releases)
- [Commits](python/mypy@v0.782...v0.790)

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

* make mypy happy

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: epwalsh <epwalsh10@gmail.com>

allennlp/common/file_utils.py

@@ -139,7 +139,7 @@ def cached_path(
     cache_dir = os.path.expanduser(cache_dir)
     os.makedirs(cache_dir, exist_ok=True)
 
-    if isinstance(url_or_filename, PathLike):
+    if not isinstance(url_or_filename, str):
         url_or_filename = str(url_or_filename)
 
     file_path: str

dev-requirements.txt

@@ -4,7 +4,7 @@
 flake8
 
 # Static type checking
-mypy==0.782
+mypy==0.790
 
 # Automatic code formatting
 black==20.8b1