pip: update edk2-pytool-extensions requirement

Updates the requirements on [edk2-pytool-extensions](https://github.com/tianocore/edk2-pytool-extensions) to permit the latest version.
- [Release notes](https://github.com/tianocore/edk2-pytool-extensions/releases)
- [Commits](tianocore/edk2-pytool-extensions@v0.27.10...v0.28.4)

---
updated-dependencies:
- dependency-name: edk2-pytool-extensions
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

pip-requirements.txt

@@ -13,7 +13,7 @@
 ##
 
 edk2-pytool-library~=0.21.9
-edk2-pytool-extensions~=0.27.10
+edk2-pytool-extensions~=0.28.4
 antlr4-python3-runtime>=4.7.1
 lcov-cobertura==2.0.2
 regex==2024.7.24