packages/tests: Fix gtest dependency

The MFC of 1d0ae66d3c (packages subdir build) added a dependency
from FreeBSD-tests on FreeBSD-googletest.  However, the googletest
package doesn't exist in 15 because the relevant commit wasn't MFC'd.
This caused a broken and unresolvable dependency.

Replace the incorrect googletest dependency with a dependency on
utilities.

This is a direct commit to stable/15.

Fixes: 1d0ae66d3c ("packages: Convert world to a subdir build")
Reviewed by:	cperciva
Reported by:	Mark Millard <[email protected]>
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D58553

packages/tests/Makefile

@@ -10,7 +10,7 @@ PKG_DEPS.tests+=	atf
 PKG_DEPS.tests+=	flua
 
 # Some tests need GoogleTest
-PKG_DEPS.tests+=	googletest
+PKG_DEPS.tests+=	utilities
 
 # The test framework requires Kyua.
 PKG_DEPS.tests+=	kyua