Distributed Tracing: Add db.query.text attribute

[joegoldman2]

It would be interesting to have the database statement being executed when using a feed interator. The standard attribute db.query.text can be used and the value can probably be QueryDefinition.QueryText

azure-cosmos-dotnet-v3/Microsoft.Azure.Cosmos/src/Query/v3Query/QueryDefinition.cs

Line 52 in 75a2e5f

public string QueryText { get; }

The statement may contain sensitive data (parameters), so this feature may require an explicit opt-in from the user. A mechanism similar to what is done in the EntityFrameworkCore instrumentation could surely be implemented:

https://github.com/open-telemetry/opentelemetry-dotnet-contrib/blob/19af5fb08264cb100e946e34855abab91dd99ed1/src/OpenTelemetry.Instrumentation.EntityFrameworkCore/EntityFrameworkInstrumentationOptions.cs#L24

A new option can be added in CosmosClientTelemetryOptions with a default value that does not activate this feature.

[joegoldman2]

Fixed by #4664.