message: cleanup template lint warnings
diff: <br>
  <IvyCodemirror
  - @value={{card}}
  - @valueUpdated={{action (mut card)}}
  + @value={{this.card}}
  + @valueUpdated={{action (mut this.card)}}
  @options={{hash
  lineNumbers=true
  mode="javascript"
  }}
  -></IvyCodemirror>
  \ No newline at end of file
  +>
  +</IvyCodemirror>
  \ No newline at end of file
  