Avoid double loop in subprocess_context.store_patches (#25621)

fixes #21643

As far as I can see the double loop is not needed, since
"patch" is never used and the items in the list are tuples
of three values.

lib/spack/spack/subprocess_context.py

@@ -139,7 +139,6 @@ def store_patches():
     class_patches = list()
     if not patches:
         return TestPatches(list(), list())
-    for patch in patches:
     for target, name, _ in patches:
         if isinstance(target, ModuleType):
             new_val = getattr(target, name)