Remove the MR description template as expected effect on user failed, see #3348

Template will disappear once this is merged to master (until then it will still appear by default in each issue, here I just deleted the suggested text)

added CI/CD label

requested review from @e.clerkin

assigned to @e.clerkin

Dear @f.uhlig, @p.-a.loizeau, @e.clerkin,

you have been identified as code owner of at least one file which was changed with this merge request.

Please check the changes and approve them or request changes.

added CodeOwners label