Auto merge of #14612 - szeged:connect-disconnect-update, r=jdm

Updating GATTServer's  Connect/Disconnect calls

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Added the missing [Step 5.2.3](https://github.com/servo/servo/compare/master...szeged:connect-disconnect-update#diff-1dbe29f87740f5aec93f37adbecace6cR213) to the `connect` function.
Updated the [disconnect](https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattserver-disconnect) function to its current state in the specification, including the `clean_up_disconnected_device` and the `garbage_collect_the connection` functions.
Added new tests for checking the invalid state of JS objects after disconnection.

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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] There are tests for these changes

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components/bluetooth_traits/lib.rs

@@ -85,12 +85,14 @@ pub type BluetoothResponseResult = Result<BluetoothResponse, BluetoothError>;
 pub enum BluetoothRequest {
     RequestDevice(RequestDeviceoptions, IpcSender<BluetoothResponseResult>),
     GATTServerConnect(String, IpcSender<BluetoothResponseResult>),
-    GATTServerDisconnect(String, IpcSender<BluetoothResult<bool>>),
+    GATTServerDisconnect(String, IpcSender<BluetoothResult<()>>),
     GetGATTChildren(String, Option<String>, bool, GATTType, IpcSender<BluetoothResponseResult>),
     ReadValue(String, IpcSender<BluetoothResponseResult>),
     WriteValue(String, Vec<u8>, IpcSender<BluetoothResponseResult>),
     EnableNotification(String, bool, IpcSender<BluetoothResponseResult>),
     WatchAdvertisements(String, IpcSender<BluetoothResponseResult>),
+    SetRepresentedToNull(Vec<String>, Vec<String>, Vec<String>),
+    IsRepresentedDeviceNull(String, IpcSender<bool>),
     Test(String, IpcSender<BluetoothResult<()>>),
     Exit,
 }