feat: Upgrade Python dependency diff-cover (#34615)

Commit generated by workflow `openedx/edx-platform/.github/workflows/upgrade-one-python-dependency.yml@refs/heads/master`

Co-authored-by: UsamaSadiq <UsamaSadiq@users.noreply.github.com>
Co-authored-by: Usama Sadiq <usama.sadiq@arbisoft.com>

requirements/edx/coverage.txt

@@ -8,7 +8,7 @@ chardet==5.2.0
     # via diff-cover
 coverage==7.4.1
     # via -r requirements/edx/coverage.in
-diff-cover==8.0.3
+diff-cover==9.0.0
     # via -r requirements/edx/coverage.in
 jinja2==3.1.3
     # via diff-cover

requirements/edx/development.txt

@@ -331,7 +331,7 @@ defusedxml==0.7.1
     #   ora2
     #   python3-openid
     #   social-auth-core
-diff-cover==8.0.3
+diff-cover==9.0.0
     # via -r requirements/edx/testing.txt
 dill==0.3.8
     # via

requirements/edx/testing.txt

@@ -250,7 +250,7 @@ defusedxml==0.7.1
     #   ora2
     #   python3-openid
     #   social-auth-core
-diff-cover==8.0.3
+diff-cover==9.0.0
     # via -r requirements/edx/coverage.txt
 dill==0.3.8
     # via pylint