Investigate direct support for OpenTelemetry tracing

EF Core currently doesn't support OpenTelemetry, but rather traces via DiagnosticSource.

An OpenTelemetry [contrib package](https://github.com/open-telemetry/opentelemetry-dotnet-contrib/tree/main/src/OpenTelemetry.Instrumentation.EntityFrameworkCore) exists for instrumenting EF Core to emit activities for command execution (containing a hard-coded translation table for the database name). We should look into providing a more 1st-class support for this.