Fix warnings: unchecked Sendable, non-async makeConnectedUser, and unused variables

[laevandus]

🎯 Goal

Seeing less warnings

📝 Summary

• Compiler requires to add unchecked Sendable
• makeConnectedUser is not async anymore (oversight from PR:3550)
• Unused variables in tests

🧪 Manual Testing Notes

N/A

☑️ Contributor Checklist

• I have signed the Stream CLA (required)
• This change should be manually QAed
• Changelog is updated with client-facing changes
• Changelog is updated with new localization keys
• New code is covered by unit tests
• Documentation has been updated in the docs-content repo

[Stream-SDK-Bot]

SDK Size

title	develop	branch	diff	status
StreamChat	6.98 MB	6.98 MB	0 KB	🟢
StreamChatUI	4.77 MB	4.77 MB	0 KB	🟢

[github-actions]

	1 Message
📖	There seems to be app changes but CHANGELOG wasn't modified. Please include an entry if the PR includes user-facing changes. You can find it at CHANGELOG.md.

Generated by 🚫 Danger

[Stream-SDK-Bot]

SDK Performance

target	metric	benchmark	branch	performance	status
MessageList	Hitches total duration	10 ms	1.67 ms	83.3% 🔼	🟢
	Duration	2.6 s	2.55 s	1.92% 🔼	🟢
	Hitch time ratio	4 ms per s	0.66 ms per s	83.5% 🔼	🟢
	Frame rate	75 fps	78.21 fps	4.28% 🔼	🟢
	Number of hitches	1	0.2	80.0% 🔼	🟢

[Stream-SDK-Bot]

SDK Size

title	develop	branch	diff	status
StreamChat	6.98 MB	6.98 MB	0 KB	🟢
StreamChatUI	4.77 MB	4.77 MB	0 KB	🟢

[sonarqubecloud]

Quality Gate passed

Issues
173 New issues
0 Accepted issues

Measures
0 Security Hotspots
83.6% Coverage on New Code
0.1% Duplication on New Code

See analysis details on SonarQube Cloud