fix: Add index in conversation and reporting event (#4577)

Fixes chatwoot/product#422

db/migrate/20220428101325_add_index_to_conversation_and_reporting_event.rb

@@ -0,0 +1,6 @@
+class AddIndexToConversationAndReportingEvent < ActiveRecord::Migration[6.1]
+  def change
+    add_index :conversations, :last_activity_at
+    add_index :reporting_events, :conversation_id
+  end
+end

db/schema.rb

@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 2022_04_24_081117) do
+ActiveRecord::Schema.define(version: 2022_04_28_101325) do
 
   # These are extensions that must be enabled in order to support this database
   enable_extension "pg_stat_statements"
@@ -361,6 +361,7 @@ ActiveRecord::Schema.define(version: 2022_04_24_081117) do
     t.index ["assignee_id", "account_id"], name: "index_conversations_on_assignee_id_and_account_id"
     t.index ["campaign_id"], name: "index_conversations_on_campaign_id"
     t.index ["contact_inbox_id"], name: "index_conversations_on_contact_inbox_id"
+    t.index ["last_activity_at"], name: "index_conversations_on_last_activity_at"
     t.index ["status", "account_id"], name: "index_conversations_on_status_and_account_id"
     t.index ["team_id"], name: "index_conversations_on_team_id"
   end
@@ -662,6 +663,7 @@ ActiveRecord::Schema.define(version: 2022_04_24_081117) do
     t.datetime "event_start_time"
     t.datetime "event_end_time"
     t.index ["account_id"], name: "index_reporting_events_on_account_id"
+    t.index ["conversation_id"], name: "index_reporting_events_on_conversation_id"
     t.index ["created_at"], name: "index_reporting_events_on_created_at"
     t.index ["inbox_id"], name: "index_reporting_events_on_inbox_id"
     t.index ["name"], name: "index_reporting_events_on_name"