bug 1615068 - enable test_osclientcerts_module.js on macOS r=kjacobs

Differential Revision: https://phabricator.services.mozilla.com/D62824

--HG--
extra : moz-landing-system : lando

security/manager/ssl/tests/unit/xpcshell-smartcards.ini

@@ -6,7 +6,7 @@ skip-if = toolkit == 'android'
 support-files =
 
 [test_osclientcerts_module.js]
-skip-if = os != 'win' || processor == 'aarch64'
+skip-if = (os != 'win' && os != 'mac') || processor == 'aarch64'
 [test_pkcs11_module.js]
 [test_pkcs11_moduleDB.js]
 [test_pkcs11_safe_mode.js]