Set fts tests language instead of depending on system default (#1276)

test/create_test_db

@@ -43,6 +43,7 @@ WHERE pg_stat_activity.datname = '$DB'
 DROP DATABASE IF EXISTS $DB;
 DROP ROLE IF EXISTS $TEST_USER_NAME;
 CREATE USER $TEST_USER_NAME WITH SUPERUSER LOGIN NOINHERIT PASSWORD '$TEST_USER_PASS' CREATEROLE;
+ALTER ROLE postgrest_test_authenticator SET default_text_search_config TO english;
 CREATE DATABASE $DB OWNER $TEST_USER_NAME LC_COLLATE 'POSIX' LC_CTYPE 'POSIX' TEMPLATE template0;
 \\connect $DB
 ALTER SCHEMA public OWNER TO $TEST_USER_NAME;