2.5 backport #40720 - fix cache timeout behavior (#41018)

* Fix cache timeout behavior

(cherry picked from commit c1400ce909)

* changelog

changelogs/fragments/fix_cache_timeout_0.yaml

@@ -0,0 +1,2 @@
+bugfixes:
+  - A cache timeout of 0 means the cache will not expire.

lib/ansible/plugins/cache/__init__.py

@@ -153,7 +153,7 @@ class BaseFileCacheModule(BaseCacheModule):
     def has_expired(self, key):
 
         if self._timeout == 0:
-            return True
+            return False
 
         cachefile = "%s/%s" % (self._cache_dir, key)
         try: