prep sst_unittest for refactor

We're pulling initializeTestModule_SingleInstance() up to SSTTestCase
so we don't need to repeat it for every subclass.

src/sst/core/testingframework/sst_unittest.py

@@ -48,6 +48,15 @@ class SSTTestCase(unittest.TestCase):
         This class is derived from Python's unittest.TestCase which provides an
         basic resource for how to develop tests for this frameworks.
     """
+    module_init = 0
+    module_sema = threading.Semaphore()
+
+    @classmethod
+    def initializeTestModule_SingleInstance(cls):
+        with cls.module_sema:
+            if cls.module_init != 1:
+                # Put your single instance Init Code Here
+                cls.module_init = 1
 
     def __init__(self, methodName):
         # NOTE: __init__ is called at startup for all tests before any