chore: Update supported Django versions

Author: sondrelg

.github/workflows/testing.yml

@@ -40,7 +40,11 @@ jobs:
       fail-fast: false
       matrix:
         python-version: [ "3.7", "3.8" , "3.9", "3.10" ]
-        django-version: [ "2.2", "3.0", "3.1", "3.2" ]
+        django-version: [ "3.0", "3.1", "3.2", "4.0" ]
+        exclude:
+          # Django v4 drops Python 3.6, and 3.7 support
+          - django-version: 4.0
+            python-version: 3.7
     steps:
       - uses: actions/checkout@v2
       - uses: actions/setup-python@v2

openapi_tester/schema_tester.py

@@ -183,7 +183,7 @@ def handle_one_of(self, schema_section: dict, data: Any, reference: str, **kwarg
             # date formats successfully, so a oneOf: date // datetime section
             # will succeed twice where it used to succeed once.
             return
-        elif matches != 1:
+        if matches != 1:
             raise DocumentationError(f"{VALIDATE_ONE_OF_ERROR.format(matches=matches)}\n\nReference: {reference}.oneOf")
 
     def handle_any_of(self, schema_section: dict, data: Any, reference: str, **kwargs: Any):