pythongh-127146: Emscripten: Set umask to zero in python.sh (python#136740)

Clears the umask used during a test of pydoc.apropos when testing on
Emscripten. This is to work around a known issue in Emscripten; but it's not
clear if the chmod call that is causing the problem is actually testing
anything of significance.

Author: hoodmane

Lib/test/test_pydoc/test_pydoc.py

@@ -1303,6 +1303,11 @@ def test_apropos_with_unreadable_dir(self):
     @os_helper.skip_unless_working_chmod
     def test_apropos_empty_doc(self):
         pkgdir = os.path.join(TESTFN, 'walkpkg')
+        if support.is_emscripten:
+            # Emscripten's readdir implementation is buggy on directories
+            # with read permission but no execute permission.
+            old_umask = os.umask(0)
+            self.addCleanup(os.umask, old_umask)
         os.mkdir(pkgdir)
         self.addCleanup(rmtree, pkgdir)
         init_path = os.path.join(pkgdir, '__init__.py')