Release 5.0.2 with error source fix for some downstream errors (#1980)

This PR fixes error source for 2 errors:
- parsing of invalid json response should be downstream error as we
expect to receive valid json from zabbix
- no host found error should be downstream. We are bumping sdk that
includes that fix
https://github.com/grafana/grafana-plugin-sdk-go/pull/1246.

As you can see - the invalid json parsing is now downstream error
<img width="1498" alt="image"
src="https://github.com/user-attachments/assets/88028dbe-0f73-47aa-8262-5729059ce12f"
/>

pkg/zabbixapi/zabbix_api.go

@@ -196,7 +196,8 @@ func isDeprecatedUserParamError(err error) bool {
 func handleAPIResult(response []byte) (*simplejson.Json, error) {
 	jsonResp, err := simplejson.NewJson([]byte(response))
 	if err != nil {
-		return nil, err
+		// Response is not valid JSON
+		return nil, backend.DownstreamError(err)
 	}
 	if errJSON, isError := jsonResp.CheckGet("error"); isError {
 		errMessage := fmt.Errorf("%s %s", errJSON.Get("message").MustString(), errJSON.Get("data").MustString())