Temporarily disable installcheck for test_oat_hooks module

Buildfarm members are encountering errors when the test is run under
various locales/encodings. As the buildfarm only does this for
installchecks, disable them for now.

Discussion: https://postgr.es/m/6067945b-960a-ab04-d40f-06b006a1dcd0@dunslane.net

Author: adunstan

src/test/modules/test_oat_hooks/Makefile

@@ -6,6 +6,9 @@ PGFILEDESC = "test_oat_hooks - example use of object access hooks"
 
 REGRESS = test_oat_hooks
 
+# disable installcheck for now
+NO_INSTALLCHECK = 1
+
 ifdef USE_PGXS
 PG_CONFIG = pg_config
 PGXS := $(shell $(PG_CONFIG) --pgxs)