Revert "[Misc] Parallelize execution of docker-based tests"
Revert "[Misc] Parallelize execution of docker-based tests"

This reverts commit 28736898e8e89bbb7cb1f31c98f0d3148021cedd.

xwiki/xwiki-platform,xwiki/xwiki-platform,xwiki/xwiki-platform,xwiki/xwiki-platform,xwiki/xwiki-platform