build: Add missing TEST_ENV_VARS to check-local target

Missed in commit 939778ab9b4147d42b7250fdb1be9c5fe79392b7.

Makecheck.am

@@ -15,6 +15,7 @@ check-clean:
 check-local: $(test_data) $(test_cases)
 	$(mkdir_p) $(test_tmpdir)
 	PATH="$(top_builddir)/src:$(top_builddir)/scripts:$(top_builddir)/utils:$(PATH)" \
+	  $(TEST_ENV_VARS) \
 	  srcdir=$(srcdir) builddir=$(builddir) \
 	  PERL5LIB=$(top_srcdir)/scripts PERL_DL_NONLAZY=1 \
 	  PERL5OPT=$(TEST_COVERAGE) \