Add OpenTelemetry tracing instrumentation for SqlClient

SqlClient itself doesn't emit OpenTelemetry tracing, but an [instrumentation package](https://github.com/open-telemetry/opentelemetry-dotnet/blob/main/src/OpenTelemetry.Instrumentation.SqlClient/README.md) exists for that; this emits traces for each command executed.

Aspire.Microsoft.Data.SqlClient currently wires up [event counter-based metrics](https://github.com/dotnet/aspire/blob/main/src/Components/Aspire.Microsoft.Data.SqlClient/AspireSqlServerSqlClientExtensions.cs#L95), but does not wire up tracing - we should add that to get traces out-of-the-box.

/cc @AndriySvyryd