[8.13](backport #4519) Fix failing upgrade command when gRPC server interrupts connection #4532
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75.0% Coverage on New Code
0.0% Duplication on New Code
What does this PR do?
The upgrade CLI command creates a client, connects to the Elastic Agent server and triggers the upgrade process which is supposed to shut down the agent and start the upgrade. Sometimes, this happens before the client gets a successful response and the upgrade command returns an error code although the upgrade succeeded.
This change checks if the connection was interrupted and treats it as a successful result instead of error.
Why is it important?
This race condition occasionally fails our integration tests.
Checklist
- [ ] I have made corresponding changes to the documentation- [ ] I have made corresponding change to the default configuration files./changelog/fragmentsusing the changelog tool- [ ] I have added an integration test or an E2E testRelated issues
This is an automatic backport of pull request Fix failing upgrade command when gRPC server interrupts connection #4519 done by Mergify.