⬆ Upgrade required Python version to >= 3.6.1, needed by typing.Deque, used by Pydantic (#2733)

Co-authored-by: Taneli Hukkinen <hukkinj1@users.noreply.github.com>
Co-authored-by: Sebastián Ramírez <tiangolo@gmail.com>

pyproject.toml

@@ -37,7 +37,7 @@ requires = [
     "pydantic >=1.6.2,!=1.7,!=1.7.1,!=1.7.2,!=1.7.3,!=1.8,!=1.8.1,<2.0.0"
 ]
 description-file = "README.md"
-requires-python = ">=3.6"
+requires-python = ">=3.6.1"
 
 [tool.flit.metadata.urls]
 Documentation = "https://fastapi.tiangolo.com/"