test: Unit test for the hs cache decrypt on new auth

Part of #30382

Signed-off-by: David Goulet <dgoulet@torproject.org>

src/feature/hs/hs_client.c

@@ -2140,4 +2140,10 @@ get_hs_client_auths_map(void)
   return client_auths;
 }
 
+STATIC void
+set_hs_client_auths_map(digest256map_t *map)
+{
+  client_auths = map;
+}
+
 #endif /* defined(TOR_UNIT_TESTS) */

src/feature/hs/hs_client.h

@@ -115,6 +115,7 @@ STATIC void retry_all_socks_conn_waiting_for_desc(void);
 #ifdef TOR_UNIT_TESTS
 
 STATIC digest256map_t *get_hs_client_auths_map(void);
+STATIC void set_hs_client_auths_map(digest256map_t *map);
 
 #endif /* defined(TOR_UNIT_TESTS) */