Fix(Structures): XXX cause event XXX to fires twice

[KhooHaoYit]

Please describe the changes this PR makes and why it should be merged:
This PR fixes similar problems like #3277 and #3252.

.delete() execute an event action handler.
After that, it got executed again by the WebSocketManager.

                Discord.js  Discord API
Call .create()      |            |
 Send API           | ---------> |
                    | <- - - - - | Execute web socket
                    |            |  Emit event
                    |            |   Check (Add)
                    |            |   handle() (Emit)
 Emit event         |            |
  Check (?Add)      |            |
  handle() (?Emit)  |            |
 Return object      |            |
                    | <- - - - - | Execute web socket
                    |            |  Emit event
                    |            |   Check (Exists)
                    |            |   handle()

Call .delete()      |            |
 Send API           | ---------> |
                    | <- - - - - | Execute web socket
                    |            |  Emit event
                    |            |   Check (Add)
                    |            |   handle() (Remove, Emit)
 Emit event         |            |
  Check (?Add)      |            |
  handle() (Remove, |            |
  1st/2nd Emit)     |            |
 Return object      |            |
                    | <- - - - - | Execute web socket
                    |            |  Emit event
                    |            |   Check (Add)
                    |            |   handle() (Remove, 2nd Emit)

Problem: The 2nd event emit is come from the .delete() or web socket.
The reason the 2nd event emits is that the object is stored to the store because of partials.

Solution: .delete() removes the object and web socket check it before doing it again.

Status

• Code changes have been tested against the Discord API, or there are no code changes
• I know how to update typings and have done so, or typings don't need updating

Semantic versioning classification:

• This PR changes the library's interface (methods or parameters added)
  • This PR includes breaking changes (methods removed or renamed, parameters moved or removed)
• This PR only includes non-code changes, like changes to documentation, README, etc.