Merge pull request #13092 from adelez/fix

Do not reuse job_specs now that we incorporate release info in the sh…
diff --git a/tools/interop_matrix/run_interop_matrix_tests.py b/tools/interop_matrix/run_interop_matrix_tests.py
index d037e13..bb7a864 100755
--- a/tools/interop_matrix/run_interop_matrix_tests.py
+++ b/tools/interop_matrix/run_interop_matrix_tests.py
@@ -122,15 +122,13 @@
   return images
 
 # caches test cases (list of JobSpec) loaded from file.  Keyed by lang and runtime.
-_loaded_testcases = {}
 def find_test_cases(lang, release, suite_name):
   """Returns the list of test cases from testcase files per lang/release."""
   file_tmpl = os.path.join(os.path.dirname(__file__), 'testcases/%s__%s')
+  testcase_release = release
   if not os.path.exists(file_tmpl % (lang, release)):
-    release = 'master'
-  testcases = file_tmpl % (lang, release)
-  if lang in _loaded_testcases.keys() and release in _loaded_testcases[lang].keys():
-    return _loaded_testcases[lang][release]
+    testcase_release = 'master'
+  testcases = file_tmpl % (lang, testcase_release)
 
   job_spec_list=[]
   try:
@@ -155,9 +153,6 @@
                      do_newline=True)
   except IOError as err:
     jobset.message('FAILED', err, do_newline=True)
-  if lang not in _loaded_testcases.keys():
-    _loaded_testcases[lang] = {}
-  _loaded_testcases[lang][release]=job_spec_list
   return job_spec_list
 
 _xml_report_tree = report_utils.new_junit_xml_tree()