Pull test_string arg out of manifest_testsuite_run_suite

(manifest_test_matches_string): Moved test matching here

(manifest_testsuite_select_tests_by_string): Use
manifest_test_matches_string to select a test.

(manifest_testsuite_run_suite): Remove matching

(manifest_manifests_run): Use
manifest_testsuite_select_tests_by_string() to match before running.