Enable MULTI_RESULTS when MULTI_STATEMENTS is enabled

To achieve as much parity as possible, let's enable MULTI_RESULTS
capability when MULTI_STATEMENTS is used. This is inline with the
assumptions the MySQL Client makes, as one implicates the other.

contrib/ruby/ext/trilogy-ruby/cext.c

@@ -444,6 +444,7 @@ static VALUE rb_trilogy_initialize(VALUE self, VALUE opts)
 
     if (RTEST(rb_hash_aref(opts, ID2SYM(id_multi_statement)))) {
         connopt.flags |= TRILOGY_CAPABILITIES_MULTI_STATEMENTS;
+        connopt.flags |= TRILOGY_CAPABILITIES_MULTI_RESULTS;
     }
 
     if ((val = rb_hash_aref(opts, ID2SYM(id_ssl_ca))) != Qnil) {