Worker Profiles - Active profile not being tracked

[shreyas-gopalakrishna]

During specialization, we want to restart job host to use the right profile in case it has changed.
Currently active profiles and existing profiles are not visible at WebHostRpcWorkerChannelManager

Currently the profile manager is initialized at the RpcWorkerConfigFactory and also at WebHostRpcWorkerChannelManager.cs . Since both are instantiated in different contexts, they currently do not share the existing profiles and active profile information. We want to mainly have one copy/instance of the profile manager so we have consistent profiles data.

Since Job host is restarted multiple times, the profile manager is initialized multiple times. To avoid this it is decided to make the service itself a global application singleton by moving it to the Webhost.

Profiles PR - #8365