Deprecate messageChannel messageFolder calendarChannel standard objects (#20836)

# Introduction

Removing old standard objects `messageChannel` and `messageFolder` and
`calendarChannel`

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Co-authored-by: Cursor <cursoragent@cursor.com>

packages/twenty-server/src/engine/workspace-manager/workspace-migration/constant/standard-object-icons.ts

@@ -6,7 +6,6 @@ export const STANDARD_OBJECT_ICONS = {
   blocklist: 'IconForbid2',
   behavioralEvent: 'IconTimelineEvent',
   calendarChannelEventAssociation: 'IconCalendar',
-  calendarChannel: 'IconCalendar',
   calendarEventParticipant: 'IconCalendar',
   calendarEvent: 'IconCalendar',
   comment: 'IconMessageCircle',
@@ -14,8 +13,6 @@ export const STANDARD_OBJECT_ICONS = {
   dashboard: 'IconLayoutDashboard',
   auditLog: 'IconTimelineEvent',
   messageChannelMessageAssociation: 'IconMessage',
-  messageChannel: 'IconMessage',
-  messageFolder: 'IconFolder',
   messageParticipant: 'IconUserCircle',
   messageThread: 'IconMessage',
   messageThreadSubscriber: 'IconPerson',