switch PHP and Ruby over to the new upb_Map_Delete()

We would like for upb_Map_Delete() to optionally return the deleted value.
Unfortunately this will require several steps since we are crossing repos.
Step #4: advance the upb version used by protobuf and update PHP/Ruby accordingly.

PiperOrigin-RevId: 498406089

Author: ericsalo

php/ext/google/protobuf/map.c

@@ -409,7 +409,7 @@ PHP_METHOD(MapField, offsetUnset) {
     return;
   }
 
-  upb_Map_Delete2(intern->map, upb_key, NULL);
+  upb_Map_Delete(intern->map, upb_key, NULL);
 }
 
 /**