Bug: httpx.ParseJsonBody don't support bytes field

[studyzy]

Describe the bug

t.Run("bytes field", func(t *testing.T) {
		type v struct {
			Signature []byte `json:"signature,optional"`
		}
		v1 := v{
			Signature: []byte{0x01, 0xff, 0x00},
		}
		body, _ := json.Marshal(v1)
		t.Logf("body:%s", string(body))
		r := httptest.NewRequest(http.MethodPost, "/", strings.NewReader(string(body)))
		r.Header.Set(ContentType, header.JsonContentType)
		if assert.NoError(t, ParseJsonBody(r, &v1)) {
			assert.Greater(t, len(v1.Signature), 0)
		}

	})

2. The error is

       requests_test.go:287: body:{"signature":"Af8A"}
    requests_test.go:290: 
        	Error Trace:	/Users/devinzeng/go/src/github.com/zeromicro/go-zero/rest/httpx/requests_test.go:290
        	Error:      	Received unexpected error:
        	            	fullName: `signature`, error: `string: `Af8A`, error: `invalid character 'A' looking for beginning of value``
        	Test:       	TestParseJsonBody/bytes_field
   

Expected behavior
No error, like json.Unmarshal

[OneThing98]

httpx.ParseJsonBody(and by extension json.Decoder) does not handle base64-encoded []byte fields by default. it is the standard convention of go. You should handle base64 decoding yourself.