Fix pgperlsyncheck following SSL TAP test refactoring

Commit 4a7e964fc6 made pgperlsyncheck fail, but apparently nobody
noticed, although the buildfarm module that does more or less the same
thing was modified. So fix the in-core test. I will look at unifying the
two sets of tests so we avoid a future mismatch.

src/tools/perlcheck/pgperlsyncheck

@@ -4,7 +4,7 @@
 
 INCLUDES="-I src/tools/msvc -I src/tools/msvc/dummylib -I src/backend/catalog"
 INCLUDES="-I src/test/perl -I src/backend/utils/mb/Unicode $INCLUDES"
-INCLUDES="-I src/bin/pg_rewind -I src/test/ssl $INCLUDES"
+INCLUDES="-I src/bin/pg_rewind -I src/test/ssl/t $INCLUDES"
 
 set -e