Add verification runtime dependencies

Add openpyxl and PyMuPDF to the release verification dependencies so clean GitHub Actions runners can execute the workbook and PDF integrity checks.

No semantic changes to MathGov Core v12.6.

Author: MathGov

requirements.txt

@@ -2,3 +2,5 @@ jsonschema>=4.20,<5
 PyYAML>=6,<7
 pypdf>=5,<7
 lxml>=5,<7
+openpyxl>=3.1,<4
+PyMuPDF>=1.26,<2