chore: let logx.SetWriter can be called anytime (#2186)

core/logx/logs.go

@@ -199,11 +199,8 @@ func SetLevel(level uint32) {
 }
 
 // SetWriter sets the logging writer. It can be used to customize the logging.
-// Call Reset before calling SetWriter again.
 func SetWriter(w Writer) {
-	if writer.Load() == nil {
-		writer.Store(w)
-	}
+	writer.Store(w)
 }
 
 // SetUp sets up the logx. If already set up, just return nil.

core/logx/logs_test.go

@@ -603,8 +603,9 @@ func TestSetWriter(t *testing.T) {
 	SetWriter(nopWriter{})
 	assert.NotNil(t, writer.Load())
 	assert.True(t, writer.Load() == nopWriter{})
-	SetWriter(new(mockWriter))
-	assert.True(t, writer.Load() == nopWriter{})
+	mocked := new(mockWriter)
+	SetWriter(mocked)
+	assert.Equal(t, mocked, writer.Load())
 }
 
 func TestWithGzip(t *testing.T) {