Merge pull request #13737 from menghanl/fix_release_matrix

Fix interop_matrix/create_matrix_images.py error

tools/interop_matrix/create_matrix_images.py

@@ -254,8 +254,9 @@ def maybe_apply_patches_on_git_tag(stack_base, lang, release):
     files_to_patch = []
     for release_info in client_matrix.LANG_RELEASE_MATRIX[lang]:
         if client_matrix.get_release_tag_name(release_info) == release:
-            files_to_patch = release_info[release].get('patch')
-            break
+            if release_info[release] is not None:
+                files_to_patch = release_info[release].get('patch')
+                break
     if not files_to_patch:
         return
     patch_file_relative_path = 'patches/%s_%s/git_repo.patch' % (lang, release)