Downgrade the ContextInitialized event from Information to Debug

[roji]

Every time a context is initialized, we log the following in Information:

info: 7/19/2022 16:59:14.052 CoreEventId.ContextInitialized[10403] (Microsoft.EntityFrameworkCore.Infrastructure) 
      Entity Framework Core 6.0.4 initialized 'BlogContext' using provider 'Microsoft.EntityFrameworkCore.SqlServer:6.0.4' with options: SensitiveDataLoggingEnabled 

That seems like pretty low-level data that should be Debug/Trace rather than Information (flagged by a user as spam in #4563).