Rename a helper inspired by an internal conversation

In a recent intense discussion during api review,
different teams have different interpretation on "silent".
One team attmpted to add some non-interactive flows into
acquire_token_silent().

That attempt to changing public API behavior was rejected.
Nonetheless, this commit aims to discourage such interpretation in the
first place by giving a more precise name to an internal helper.

Author: rayluo

msal/application.py

@@ -400,20 +400,21 @@ def acquire_token_silent(
         #     authority,
         #     verify=self.verify, proxies=self.proxies, timeout=self.timeout,
         #     ) if authority else self.authority
-        result = self._acquire_token_silent(scopes, account, self.authority, **kwargs)
+        result = self._acquire_token_silent_from_cache_and_possibly_refresh_it(
+            scopes, account, self.authority, **kwargs)
         if result:
             return result
         for alias in self._get_authority_aliases(self.authority.instance):
             the_authority = Authority(
                 "https://" + alias + "/" + self.authority.tenant,
                 validate_authority=False,
                 verify=self.verify, proxies=self.proxies, timeout=self.timeout)
-            result = self._acquire_token_silent(
+            result = self._acquire_token_silent_from_cache_and_possibly_refresh_it(
                 scopes, account, the_authority, **kwargs)
             if result:
                 return result
 
-    def _acquire_token_silent(
+    def _acquire_token_silent_from_cache_and_possibly_refresh_it(
             self,
             scopes,  # type: List[str]
             account,  # type: Optional[Account]