Update dependency google-cloud-trace to v0.24.0 (GoogleCloudPlatform#4579)

Author: renovate-bot

trace/cloud-trace-demo-app-opentelemetry/app/requirements.txt

@@ -11,5 +11,5 @@ opentelemetry-sdk==0.9b0
 grpcio==1.31.0
 httpretty==1.0.2
 google-cloud-monitoring==1.1.0
-google-cloud-trace==0.23.0
+google-cloud-trace==0.24.0