fix: emitting onEndMention event - android (#317)

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# Summary

Fixes:
#312
## Test Plan

- Start a `@` mention and click an option in your UI that calls
`setMention`
- Notice that `onEndMention` is called after setting mention

## Screenshots / Videos

n/a

## Compatibility

| OS      | Implemented |
| ------- | :---------: |
| iOS     |    ❌     |
| Android |    ✅     |

Author: exploIF

android/src/main/java/com/swmansion/enriched/events/MentionHandler.kt

@@ -9,8 +9,8 @@ class MentionHandler(private val view: EnrichedTextInputView) {
   private var previousIndicator: String? = null
 
   fun reset() {
+    endMention()
     previousText = null
-    previousIndicator = null
   }
 
   fun endMention() {

example/src/App.tsx

@@ -262,15 +262,13 @@ export default function App() {
       id: item.id,
       type: 'user',
     });
-    closeUserMentionPopup();
   };
 
   const handleChannelMentionSelected = (item: MentionItem) => {
     ref.current?.setMention('#', `#${item.name}`, {
       id: item.id,
       type: 'channel',
     });
-    closeChannelMentionPopup();
   };
 
   const handleFocusEvent = () => {