test: make use of platform token

Try to debug if the EOF is related to the oauth2 lib

Author: Kirdock

.github/workflows/tests.yml

@@ -50,4 +50,5 @@ jobs:
           DT_CLIENT_ID: ${{ secrets.DT_CLIENT_ID }}
           DT_CLIENT_SECRET: ${{ secrets.DT_CLIENT_SECRET }}
           DT_ACCOUNT_ID: ${{ secrets.DT_ACCOUNT_ID }}
+          DYNATRACE_PLATFORM_TOKEN: ${{ secrets.DYNATRACE_PLATFORM_TOKEN }}
         run: go test -tags=integration -v ./...