t/t9602-cvsimport-branches-tags.sh: Add a PERL prerequisite

Change this test to declare a PERL prerequisite. These tests use the
-p switch, so they implicitly depend on Perl code, but nothing was
declaring this.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t/t9602-cvsimport-branches-tags.sh

@@ -6,70 +6,72 @@
 test_description='git cvsimport handling of branches and tags'
 . ./lib-cvs.sh
 
-CVSROOT="$TEST_DIRECTORY"/t9602/cvsroot
-export CVSROOT
+test_expect_success PERL 'setup CVSROOT' '
+	CVSROOT="$TEST_DIRECTORY"/t9602/cvsroot &&
+	export CVSROOT
+'
 
-test_expect_success 'import module' '
+test_expect_success PERL 'import module' '
 
 	git cvsimport -C module-git module
 
 '
 
-test_expect_success 'test branch master' '
+test_expect_success PERL 'test branch master' '
 
 	test_cmp_branch_tree master
 
 '
 
-test_expect_success 'test branch vendorbranch' '
+test_expect_success PERL 'test branch vendorbranch' '
 
 	test_cmp_branch_tree vendorbranch
 
 '
 
-test_expect_failure 'test branch B_FROM_INITIALS' '
+test_expect_failure PERL 'test branch B_FROM_INITIALS' '
 
 	test_cmp_branch_tree B_FROM_INITIALS
 
 '
 
-test_expect_failure 'test branch B_FROM_INITIALS_BUT_ONE' '
+test_expect_failure PERL 'test branch B_FROM_INITIALS_BUT_ONE' '
 
 	test_cmp_branch_tree B_FROM_INITIALS_BUT_ONE
 
 '
 
-test_expect_failure 'test branch B_MIXED' '
+test_expect_failure PERL 'test branch B_MIXED' '
 
 	test_cmp_branch_tree B_MIXED
 
 '
 
-test_expect_success 'test branch B_SPLIT' '
+test_expect_success PERL 'test branch B_SPLIT' '
 
 	test_cmp_branch_tree B_SPLIT
 
 '
 
-test_expect_failure 'test tag vendortag' '
+test_expect_failure PERL 'test tag vendortag' '
 
 	test_cmp_branch_tree vendortag
 
 '
 
-test_expect_success 'test tag T_ALL_INITIAL_FILES' '
+test_expect_success PERL 'test tag T_ALL_INITIAL_FILES' '
 
 	test_cmp_branch_tree T_ALL_INITIAL_FILES
 
 '
 
-test_expect_failure 'test tag T_ALL_INITIAL_FILES_BUT_ONE' '
+test_expect_failure PERL 'test tag T_ALL_INITIAL_FILES_BUT_ONE' '
 
 	test_cmp_branch_tree T_ALL_INITIAL_FILES_BUT_ONE
 
 '
 
-test_expect_failure 'test tag T_MIXED' '
+test_expect_failure PERL 'test tag T_MIXED' '
 
 	test_cmp_branch_tree T_MIXED