fix(registry): resolve golangci-lint issues in token-auth tests

- Use (*net.ListenConfig).Listen with the test context instead of
  net.Listen (noctx).
- Use suite.NoError instead of suite.Nil for the error check
  (testifylint).
- Drop the unnecessary leading blank lines in the scope test funcs
  (whitespace).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Signed-off-by: kimsm28 <sm28.kim@samsung.com>

pkg/registry/client_scope_test.go

@@ -46,7 +46,6 @@ func (suite *RegistryScopeTestSuite) TearDownSuite() {
 }
 
 func (suite *RegistryScopeTestSuite) Test_1_Check_Push_Request_Scope() {
-
 	requestURL := make(chan string, 1)
 	handler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		// Capture only the first auth request; never block the handler if the
@@ -58,7 +57,8 @@ func (suite *RegistryScopeTestSuite) Test_1_Check_Push_Request_Scope() {
 		}
 		w.WriteHeader(http.StatusOK)
 	})
-	listener, err := net.Listen("tcp", suite.AuthServerHost)
+	lnCfg := net.ListenConfig{}
+	listener, err := lnCfg.Listen(suite.T().Context(), "tcp", suite.AuthServerHost)
 	suite.NoError(err, "no error creating server listener")
 
 	ts := httptest.NewUnstartedServer(handler)
@@ -92,7 +92,6 @@ func (suite *RegistryScopeTestSuite) Test_1_Check_Push_Request_Scope() {
 }
 
 func (suite *RegistryScopeTestSuite) Test_2_Check_Pull_Request_Scope() {
-
 	requestURL := make(chan string, 1)
 	handler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		// Capture only the first auth request; never block the handler if the
@@ -104,7 +103,8 @@ func (suite *RegistryScopeTestSuite) Test_2_Check_Pull_Request_Scope() {
 		}
 		w.WriteHeader(http.StatusOK)
 	})
-	listener, err := net.Listen("tcp", suite.AuthServerHost)
+	lnCfg := net.ListenConfig{}
+	listener, err := lnCfg.Listen(suite.T().Context(), "tcp", suite.AuthServerHost)
 	suite.NoError(err, "no error creating server listener")
 
 	ts := httptest.NewUnstartedServer(handler)

pkg/registry/registry_test.go

@@ -147,8 +147,8 @@ func setup(suite *TestRegistry, tlsEnabled, insecure bool, auth string) {
 	config.Storage = map[string]configuration.Parameters{"inmemory": map[string]any{}}
 
 	if auth == "token" {
-		ln, err := net.Listen("tcp", "127.0.0.1:0")
-		suite.Nil(err, "no error finding free port for test auth server")
+		ln, err := lnCfg.Listen(suite.T().Context(), "tcp", "127.0.0.1:0")
+		suite.NoError(err, "no error finding free port for test auth server")
 		defer ln.Close()
 
 		//set test auth server host