fix(msteams): remove optional deps from dev extras and gate tests

PyJWT and cryptography are optional msteams deps; they should not be
bundled into the generic dev install.  Tests now skip the entire file
when the deps are missing, following the dingtalk pattern.

pyproject.toml

@@ -93,7 +93,6 @@ dev = [
     "aiohttp>=3.9.0,<4.0.0",
     "pytest-cov>=6.0.0,<7.0.0",
     "ruff>=0.1.0",
-    "pymupdf>=1.25.0",
 ]
 
 [project.scripts]