Bump typing-extensions from 4.4.0 to 4.15.0

Bumps [typing-extensions](https://github.com/python/typing_extensions) from 4.4.0 to 4.15.0.
- [Release notes](https://github.com/python/typing_extensions/releases)
- [Changelog](https://github.com/python/typing_extensions/blob/main/CHANGELOG.md)
- [Commits](python/typing_extensions@4.4.0...4.15.0)

---
updated-dependencies:
- dependency-name: typing-extensions
  dependency-version: 4.15.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

backend/requirements.txt

@@ -233,9 +233,9 @@ starlette==0.19.1 ; python_version >= "3.8" and python_version < "4.0" \
 toml==0.10.2 ; python_version >= "3.8" and python_version < "4.0" \
     --hash=sha256:806143ae5bfb6a3c6e736a764057db0e6a0e05e338b5630894a5f779cabb4f9b \
     --hash=sha256:b3bda1d108d5dd99f4a20d24d9c348e91c4db7ab1b749200bded2f839ccbe68f
-typing-extensions==4.4.0 ; python_version >= "3.8" and python_version < "4.0" \
-    --hash=sha256:1511434bb92bf8dd198c12b1cc812e800d4181cfcb867674e0f8279cc93087aa \
-    --hash=sha256:16fa4864408f655d35ec496218b85f79b3437c829e93320c7c9215ccfd92489e
+typing-extensions==4.15.0 ; python_version >= "3.8" and python_version < "4.0" \
+    --hash=sha256:0cea48d173cc12fa28ecabc3b837ea3cf6f38c6d1136f85cbaaf598984861466 \
+    --hash=sha256:f0fa19c6845758ab08074a0cfa8b7aecb71c999ca73d62883bc25cc018c4e548
 uvicorn==0.18.3 ; python_version >= "3.8" and python_version < "4.0" \
     --hash=sha256:0abd429ebb41e604ed8d2be6c60530de3408f250e8d2d84967d85ba9e86fe3af \
     --hash=sha256:9a66e7c42a2a95222f76ec24a4b754c158261c4696e683b9dadc72b590e0311b