DD_TRACE_DELAY_WCF_INSTRUMENTATION_ENABLED Prevents Traces

[austin-tcetra]

Describe the bug
When the env variable DD_TRACE_DELAY_WCF_INSTRUMENTATION_ENABLED is set to true, trace ids are lost.

To Reproduce

1. Given the below runtime environment, our app consistently had trace ids associated with its logs.
2. In troubleshooting a separate issue we were experiencing, we added the DD_TRACE_DELAY_WCF_INSTRUMENTATION_ENABLED env variable and set it to true.
3. Our app that was consistently showing trace ids in DD stopped showing any trace ids.
4. We tried multiple versions of the tracer (see below) with no change.
5. We set the variable to false, with no change.
6. We removed the variable and immediately saw full logs again.

Expected behavior
The presence of DD_TRACE_DELAY_WCF_INSTRUMENTATION_ENABLED as an environment variable should not affect the presence of trace_ids in the logs

Runtime environment (please complete the following information):

• Instrumentation mode: datadog-dotnet-apm-2.47.0-x64.msi etc,
• Tracer version: 2.47.0, 2.49.0, 2.56.0
• OS: Windows Server 2022 Datacenter, Version 10.0.20348 Build 20348
• CLR: .NET Framework 4.8

Additional context

• We tried adding the env var based on reading this pr.