Error when uploading 'junit' artifact: gzip.Write: non-Latin-1 header string
### Summary
When uploading multiple XML artifacts of type `junit`, the CI fails with `gzip.Write: non-Latin-1 header string`:
```
ERROR: Uploading artifacts as "junit" to coordinator... error correlation_id=d23413b716a34805b8d58c3430cc3eea error=execute raw request: execute request: couldn't execute POST against https://gitlab.com/api/v4/jobs/12096492027/artifacts?artifact_format=gzip&artifact_type=junit: Post "https://gitlab.com/api/v4/jobs/12096492027/artifacts?artifact_format=gzip&artifact_type=junit": failed to copy content to form: gzip.Write: non-Latin-1 header string id=12096492027 token=6b_ecgQCU
```
### Steps to reproduce
1. Open https://gitlab.com/opensavvy/ktmongo/-/jobs/12096492027
2. Retry the job
The job itself does NOT build GZIP files, it only builds regular `.xml` files. It is the runner that gzips them, and I don't see how the GZIP headers would be impacted by the contents of the files, so this shouldn't be a problem of the project itself.
### What is the current *bug* behavior?
The job fails with a GZIP header error, as shown before.
### What is the expected *correct* behavior?
The job is successful and the junit artifact is uploaded.
### Output of checks
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issue