Force NO_LOCALE / UTF8 for test_oat_hooks tests

This will fix cases like fairywren that have been having issues.

Discussion: https://postgr.es/m/2630561.1647994022@sss.pgh.pa.us

Author: adunstan

src/test/modules/test_oat_hooks/Makefile

@@ -10,6 +10,9 @@ REGRESS = test_oat_hooks
 
 # disable installcheck for now
 NO_INSTALLCHECK = 1
+# and also for now force NO_LOCALE and UTF8
+ENCODING = UTF8
+NO_LOCALE = 1
 
 ifdef USE_PGXS
 PG_CONFIG = pg_config