[PB-3099] feat: remove deferred class usage from OlmAdapter

[apsantiso]

Removed usage of Deferred class from OlmAdapter.

• SessionInitializationInProgress variable added to prevent multiple calls to initSessions.
• this._init is used just to check if the OLM adapter is initialized, it should be initialized when users access to the meeting as it loads even if e2ee is not enabled.
• Deferred was deprecated. We just started using raw Promises, the pattern of resolving promises after a while is not avoidable as this flow is pretty async and we rely on users sending back ACK messages.

To consider:

• There are still some problems like the audio sometimes not working as expected if you enable e2ee, however, you can check that the encryption keys are being shared successfully from the keys manager.
• Like on the original implementation, when a moderator enables e2ee, it enables that feature for ALL users in the meeting, this triggers an _onParticipantPropertyChanged event, which calls sendKeyInfoToAll event, which leads to sometimes seeing messages such as "session not initialized with user xxxxxx". This is not related to any race issues and keys should be shared with users despite this.
  Check:

  lib-jitsi-meet/modules/e2ee/OlmAdapter.ts

  Line 1466 in 7ed4487

  await this.sendKeyInfoToAll();

• I had performance problems while debugging the project due to trophy logging too many times things to the console while on DEBUG mode, you can avoid this by commenting out one line, it makes debugging much faster.

[TamaraFinogina]

It's not working for me. I'm getting uncaught runtime errors that kill the meeting the moment e2e is turned on. I've tried to start a meeting many times and the best I could get is two users out of 3 have a session maybe once every several tries.

UPDATE The problem was solved after updating jitsi-meet

[TamaraFinogina]

It should be still await, no?