Update .gitlab-ci.yml after addition of luaposix test

Commit a0b0976c9333 (support/testing: add luaposix test) added a new test,
but forgot to update .gitlab-ci.yml.  Do that now.

Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

.gitlab-ci.yml

@@ -383,6 +383,8 @@ tests.package.test_luafilesystem.TestLuaLuaFileSystem: { extends: .runtime_test
 tests.package.test_luafilesystem.TestLuajitLuaFileSystem: { extends: .runtime_test }
 tests.package.test_luaossl.TestLuaLuaossl: { extends: .runtime_test }
 tests.package.test_luaossl.TestLuajitLuaossl: { extends: .runtime_test }
+tests.package.test_luaposix.TestLuaLuaPosix: { extends: .runtime_test }
+tests.package.test_luaposix.TestLuajitLuaPosix: { extends: .runtime_test }
 tests.package.test_luasec.TestLuaLuaSec: { extends: .runtime_test }
 tests.package.test_luasec.TestLuajitLuaSec: { extends: .runtime_test }
 tests.package.test_luasocket.TestLuaLuaSocket: { extends: .runtime_test }