flask-debug-3933: update to set debug explicitly to False (#3956)

Author: keithkroeger

CHANGELOG.md

@@ -7,6 +7,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## Unreleased
 
+- Do not execute Flask Tests in debug mode
+  ([#3956](https://github.com/open-telemetry/opentelemetry-python/pull/3956))
 - When encountering an error encoding metric attributes in the OTLP exporter, log the key that had an error.
   ([#3838](https://github.com/open-telemetry/opentelemetry-python/pull/3838))
 - Log a warning when a `LogRecord` in `sdk/log` has dropped attributes

tests/w3c_tracecontext_validation_server.py

@@ -70,6 +70,6 @@ def verify_tracecontext():
 
 if __name__ == "__main__":
     try:
-        app.run(debug=True)
+        app.run(debug=False)
     finally:
         span_processor.shutdown()