cache option to fetchOwnProfileFromServer and missing awaits in group call enter/leave

Description

Fixes #

Kept default value of cache to false because the function name suggests we will be fetching the profile from the server by default

Checklist

• I read the [Contributor Guide] and followed the process outlined there for submitting PRs.
• I updated/added relevant documentation (doc comments with ///).
• I did not add or update methods, functions or widgets without tests.