Trace duplication on development deployment

[qtomlinson]

Problem:
We were seeing each log event appear twice in traces.

• One entry had our expected custom properties, and
• a second entry appeared at nearly the same timestamp without those properties.

Root cause:
Two telemetry pipelines were active at the same time.

PR #749 attempts to address this, but the trace duplication remains.

[qtomlinson]

After further analysis, the root cause is:
Two telemetry pipelines were active at the same time:

• Our in-application logging pipeline (custom Winston/Application Insights path), and
• A platform/legacy Application Insights auto-instrumentation path.
  Both were exporting the same log events, which created duplicate traces.

Action taken:
To keep a single telemetry path, I removed these platform/legacy settings from cdcrawler-dev:

• APPLICATIONINSIGHTS_CONNECTION_STRING
• APPLICATIONINSIGHTS_CONFIGURATION_CONTENT
• APPINSIGHTS_INSTRUMENTATIONKEY (this one does the trick in our case)
• ApplicationInsightsAgent_EXTENSION_VERSION (if not removed, led to warning of invalid instrumentation key)

Keep only one telemetry path: in-app CRAWLER_INSIGHTS_CONNECTION_STRING setup.

Result:
Duplicate traces stopped, and telemetry continues to flow correctly through our application-level configuration.

In light of these configuration changes, PR #749 still acts as a safe guard in our code base and documents the intent that telemetry should flow only through custom transport and therefore is kept in place.