feat: Replace alertMixin usage with useAlert (#9793)

# Pull Request Template

## Description

This PR will replace the usage of `alertMixin` from the code base with
the `useAlert` composable.

Fixes
https://linear.app/chatwoot/issue/CW-3462/replace-alertmixin-usage-with-usealert

## Type of change

- [x] Breaking change (fix or feature that would cause existing
functionality not to work as expected)

## How Has This Been Tested?

Please refer this issue description

https://linear.app/chatwoot/issue/CW-3462/replace-alertmixin-usage-with-usealert


## Checklist:

- [x] My code follows the style guidelines of this project
- [x] I have performed a self-review of my code
- [ ] I have commented on my code, particularly in hard-to-understand
areas
- [ ] I have made corresponding changes to the documentation
- [x] My changes generate no new warnings
- [x] I have added tests that prove my fix is effective or that my
feature works
- [x] New and existing unit tests pass locally with my changes
- [ ] Any dependent changes have been merged and published in downstream
modules

---------

Co-authored-by: Sojan Jose <sojan@pepalo.com>

app/javascript/dashboard/components/buttons/ResolveAction.vue

@@ -78,7 +78,7 @@
 
 <script>
 import { mapGetters } from 'vuex';
-import alertMixin from 'shared/mixins/alertMixin';
+import { useAlert } from 'dashboard/composables';
 import keyboardEventListenerMixins from 'shared/mixins/keyboardEventListenerMixins';
 import WootDropdownItem from 'shared/components/ui/dropdown/DropdownItem.vue';
 import WootDropdownMenu from 'shared/components/ui/dropdown/DropdownMenu.vue';
@@ -94,7 +94,7 @@ export default {
     WootDropdownItem,
     WootDropdownMenu,
   },
-  mixins: [alertMixin, keyboardEventListenerMixins],
+  mixins: [keyboardEventListenerMixins],
   props: { conversationId: { type: [String, Number], required: true } },
   data() {
     return {
@@ -209,7 +209,7 @@ export default {
           snoozedUntil,
         })
         .then(() => {
-          this.showAlert(this.$t('CONVERSATION.CHANGE_STATUS'));
+          useAlert(this.$t('CONVERSATION.CHANGE_STATUS'));
           this.isLoading = false;
         });
     },