Update mypy requirement from <0.1000,>=0.991 to >=0.991,<1.1

Updates the requirements on [mypy](https://github.com/python/mypy) to permit the latest version.
- [Release notes](https://github.com/python/mypy/releases)
- [Commits](python/mypy@v0.991...v1.0.0)

---
updated-dependencies:
- dependency-name: mypy
  dependency-type: direct:production
...

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

Author: dependabot[bot]

setup.py

@@ -28,7 +28,7 @@ def find_stub_files(name):
 ]
 
 extras_require = {
-    "compatible-mypy": ["mypy>=0.991,<0.1000"],
+    "compatible-mypy": ["mypy>=0.991,<1.1"],
     "coreapi": ["coreapi>=2.0.0"],
     "markdown": ["types-Markdown>=0.1.5"],
 }