Apply suggestions from code review

Author: mik-laj

.pre-commit-config.yaml

@@ -13,11 +13,10 @@ repos:
     hooks:
       - id: pyupgrade
         args: ["--py36-plus"]
-        exclude: ^airflow/_vendor/
   - repo: local
     hooks:
       - id: flynt
         name: Convert to f-strings with flynt
         entry: flynt
         language: python
-        additional_dependencies: ['flynt==0.64']
+        additional_dependencies: ['flynt==0.64']

openapi_core/templating/media_types/exceptions.py

@@ -18,4 +18,4 @@ def __str__(self):
         return (
             f"Content for the following mimetype not found: {self.mimetype}. "
             f"Valid mimetypes: {self.availableMimetypes}"
-        )
+        )