Added exception handler to trap the RuntimeError raised when

Depends.enforce_dependency() class method fires unsuccessfully. There appears
to be no synchronization within the Depends decorator class wrt the
class global dependency_dict which results in incomplete population of any
loader instantiation occuring at the time of one of these exceptions.

This would mitigate the immediate affects of saltstack#23839 and saltstack#23373.

salt/loader.py

@@ -1065,7 +1065,12 @@ def _load_module(self, name):
             self._apply_outputter(func, mod)
 
         # enforce depends
-        Depends.enforce_dependencies(self._dict, self.tag)
+        try:
+            Depends.enforce_dependencies(self._dict, self.tag)
+        except RuntimeError as e:
+            log.info('Depends.enforce_dependencies() failed '
+                     'for reasons: '.format(e))
+
         self.loaded_modules[module_name] = mod_dict
         return True