fix: Remove unnecessary import in the TTIPlugin (#475)

Author: ps863

src/plugins/event-plugins/TTIPlugin.ts

@@ -1,7 +1,6 @@
 import { TTIMetric, onTTI } from '../../time-to-interactive/TimeToInteractive';
 import { TimeToInteractiveEvent } from '../../events/time-to-interactive-event';
 import { TIME_TO_INTERACTIVE_EVENT_TYPE } from '../utils/constant';
-import { PluginContext } from 'plugins/types';
 import { InternalPlugin } from '../InternalPlugin';
 
 export const TTI_EVENT_PLUGIN_ID = 'time-to-interactive';
@@ -14,8 +13,6 @@ export class TTIPlugin extends InternalPlugin {
         this.fpsEnabled = fpsMeasurementEnabled;
     }
 
-    protected context!: PluginContext;
-
     enable(): void {
         /* Nothing to do. */
     }