Fix test_errors_in_xfail_skip_expressions for Python 3.10.1

Decided to remove the condition altogether as seems reasonable to state
that our own test suite requires Python 3.10.1.

Fix #9413

Author: nicoddemus

testing/test_skipping.py

@@ -1143,8 +1143,6 @@ def test_func():
     pypy_version_info = getattr(sys, "pypy_version_info", None)
     if pypy_version_info is not None and pypy_version_info < (6,):
         markline = markline[5:]
-    elif sys.version_info[:2] >= (3, 10):
-        markline = markline[11:]
     elif sys.version_info >= (3, 8) or hasattr(sys, "pypy_version_info"):
         markline = markline[4:]