improve: hide loading validator image (#4287)

* hide missing validator image

* Render nothing if validator badge has not loaded/received errors

* Revert style changes

Author: heldersepu

src/core/components/online-validator-badge.jsx

@@ -101,7 +101,7 @@ class ValidatorImage extends React.Component {
     if (this.state.error) {
       return <img alt={"Error"} />
     } else if (!this.state.loaded) {
-      return <img alt= {"Loading..."} />
+      return null
     }
     return <img src={this.props.src} alt={this.props.alt} />
   }