[8.0] dmeta - Error message in case failure due to permission denied

[atsareg]

Make error message in case of metadata manipulation permission failre, e.g.:

$ dmeta add testfile Year="1997"
Error: /vo.formation.idgrilles.fr/user/a/atsareg/testmeta/testfile Permission denied ( 13 : Permission denied)

Otherwise, no message at all

BEGINRELEASENOTES

*Interfaces
CHANGE: dfind - more explicit failure report

ENDRELEASENOTES

[sfayer]

Looks reasonable to me.

Regards,
Simon

[DIRACGridBot]

Sweep summary

Sweep ran in https://github.com/DIRACGrid/DIRAC/actions/runs/7898744875

Failed:

• integration
  cherry-pick 3081d48 into integration failed
  check merge conflicts on a local copy of this repository

  git fetch upstream
  git checkout upstream/integration -b cherry-pick-2-3081d4813-integration
  git cherry-pick -x -m 1 3081d4813
  # Fix the conflicts
  git cherry-pick --continue
  git commit --amend -m 'sweep: #7465 dmeta - Error message in case failure due to permission denied' --author='Andrei Tsaregorodtsev <[email protected]>'
  git push -u origin cherry-pick-2-3081d4813-integration
  
  # If you have the GitHub CLI installed the PR can be made with
  gh pr create \
       --label 'sweep:from rel-v8r0' \
       --base integration \
       --repo DIRACGrid/DIRAC \
       --title '[sweep:integration] dmeta - Error message in case failure due to permission denied' \
       --body 'Sweep #7465 `dmeta - Error message in case failure due to permission denied` to `integration`.
  
  Adding original author @atsareg as watcher.
  
  BEGINRELEASENOTES
  
  *Interfaces
  CHANGE: dfind - more explicit failure report
  
  ENDRELEASENOTES
  Closes #7469'