[MM-14725] Inform System Admins when a user who managed bot ac… (#11669)

* Add notification, to sysadmins, when a user is disabled and the user
owns bots.

* If the user doesn't have any bots, there is no need to send a
notifcation to sysadmins

* Remove comment

* Update documention link

* Send as System

* Query teams for each sysadmin and add first response to hardcoded link.

* Remove fmt.print debug statements

* remove link with hard-coded team.  Will add this as future enhancement
Expose GetDisableBotSysadminMessage function so it can be tested
Add test new function for testing new notification feature

* Fix shadow error

* Swap sentences in the message when  System Console > Bot Accounts > Disable bot accounts when owner is deactivated: is set to false

* Another message correction

* Rename Custom Integrations to Integrations

* rename botsDisabled variable to disableBotsSetting

* - increase the number of bots and sysadmins queried to 1000.
- limit the number of bots printed in the post to 10, but mention the
  total bots owned by the user

* Enable translations for sysadmin messages

* - Rename function. The actual purpose for the function is to notify
  sysadmins that a user, that owned bots, was disabled.
- convert GetDisableBotSysadminMessage from a function to a method.
  This allows getting *a.Config().ServiceSettings.DisableBotsWhenOwnerIsDeactivated
  in the method and avoids having to pass the value as an input to a
  function

* fix "make i18n-extract" error.  Reorganize .json file

* Correct the upper range value to be the minimum of number of elements in the
userBots array, or the upper limit (10)

* replace t.fatal with require statements
fix golangci-lint errors

* Create separate message when user managed less than or fewer than 10 bots
Test cases for both message types

* fix i18n sorting

* Using pagination to get the bots and sysadmins instead of setting
arbitrary value for PerPage and only retrieving first page

* only use one translation ID for the message.
push all logic into the template so translators can view the logic
add disableBotsSetting and printAllBots variables to the translation
map

* Break the for loop once len(bots) < perPage value, instead of
breaking once there are no bots. This saves one additional call

model/post.go

@@ -243,6 +243,7 @@ func (o *Post) IsValid(maxPostSize int) *AppError {
 	switch o.Type {
 	case
 		POST_DEFAULT,
+		POST_SYSTEM_GENERIC,
 		POST_JOIN_LEAVE,
 		POST_AUTO_RESPONDER,
 		POST_ADD_REMOVE,