pip: bump regex from 2026.2.19 to 2026.2.28 (#472)

Bumps [regex](https://github.com/mrabarnett/mrab-regex) from 2026.2.19
to 2026.2.28.

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

pip-requirements.txt

@@ -16,5 +16,5 @@ edk2-pytool-library~=0.23.11
 edk2-pytool-extensions~=0.30.8
 antlr4-python3-runtime==4.13.2
 lcov-cobertura==2.1.1
-regex==2026.2.19
+regex==2026.2.28
 pygount==3.1.1