chore: Add help-text for slack integration (#2409)

app/javascript/dashboard/i18n/locale/en/integrations.json

@@ -63,6 +63,12 @@
         }
       }
     },
+    "SLACK": {
+      "HELP_TEXT" : { 
+        "TITLE": "Using Slack Integration",
+        "BODY": "<br/><p>Chatwoot will now sync all the incoming conversations into the <b><i>customer-conversations</i></b> channel inside your slack workplace.</p><p>Replying to a conversation thread in <b><i>customer-conversations</i></b> slack channel will create a response back to the customer through chatwoot.</p><p>Start the replies with <b><i>note:</i></b> to create private notes instead of replies.</p><p>If the replier on slack has an agent profile in chatwoot under the same email, the replies will be associated accordingly.</p><p>When the replier doesn't have an associated agent profile, the replies will be made from the bot profile.</p>" 
+      }
+    },
     "DELETE": {
       "BUTTON_TEXT": "Delete",
       "API": {