t9200: replace test -f/-d with modern path helpers

Replace old style 'test -f' and 'test -d' with helpers
'test_path_is_file' and 'test_path_is_dir' respectively,
which make debugging a failing test easier by loudly
reporting what expectation was not met.

The instances were found with:

	git grep "test -[efd]" t/

Signed-off-by: Pablo Sabater <pabloosabaterr@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t/t9200-git-cvsexportcommit.sh

@@ -31,7 +31,7 @@ export CVSROOT CVSWORK GIT_DIR
 rm -rf "$CVSROOT" "$CVSWORK"
 
 cvs init &&
-test -d "$CVSROOT" &&
+test_path_is_dir "$CVSROOT" &&
 cvs -Q co -d "$CVSWORK" . &&
 echo >empty &&
 git add empty &&
@@ -303,7 +303,7 @@ test_expect_success 're-commit a removed filename which remains in CVS attic' '
 	git commit -m "Added attic_gremlin" &&
 	git cvsexportcommit -w "$CVSWORK" -c HEAD &&
 	(cd "$CVSWORK" && cvs -Q update -d) &&
-	test -f "$CVSWORK/attic_gremlin"
+	test_path_is_file "$CVSWORK/attic_gremlin"
 '
 
 # the state of the CVS sandbox may be indeterminate for ' space'