Remove the sync method for background job module.

[maliming]

#2464 (comment)

[hikalkan]

Background job is OK, but we shouldn't change the tenant store. Why? Let me explain;

First of all, IConnectionStringResolver.Resolve method is sync by its nature. We can not change it, unfortunately.

For RemoteTenantStore.cs;

• When we use AsyncHelper inside the Resolve method, AsyncHelper is always called, in every request. But if we move AsyncHelper usage to the RemoteTenantStore (like my implementation), it is called only if it can not find the connection string in the cache.

For TenantStore.cs;

• If we remove the sync Find method, we force to AsyncHelper usage unnecessarily while we could implement it truely sync. Native sync is better than async over sync usage.

So, please cancel the tenantstore changes for now, until we find a good way to make IConnectionStringResolver.Resolve async.

[maliming]

I have cancelled related changes to tenant.

[hikalkan]

Thanks ;)