gitlab-ci: don't upload the static osmesa binary

It's just for testing.
10 jobs for !760 with gitlab-ci-no-upload-static-osmesa in 54 minutes and 15 seconds (queued for 4 seconds)
merge request
Name Stage Failure
test:linux-plain Test

Running after_script
Uploading artifacts for failed job
Uploading artifacts...
build/ParaView-*.tar.*: found 1 matching files

WARNING: build/ParaView-*.dmg: no matching files
WARNING: build/ParaView-*.zip: no matching files
Uploading artifacts to coordinator... ok
id=5135877 responseStatus=201 Created token=yWy8fwvz
ERROR: Job failed: exit code 1