Merge branch 'ci-extract-tar' into 'master'

ci: respdiff - extract multiple archives

See merge request !853

.gitlab-ci.yml

@@ -352,7 +352,7 @@ pytests:
   after_script:
     - 'cp -t . respdiff_commitdir/$RESPDIFF_TEST/j* ||:'
     - 'cp -t . respdiff_commitdir/*$RESPDIFF_TEST*.png ||:'
-    - 'tar xf respdiff_commitdir/$RESPDIFF_TEST/*histogram.tar.gz ||:'
+    - 'cat respdiff_commitdir/$RESPDIFF_TEST/*histogram.tar.gz | tar -xf - -i ||:'
   artifacts:
     when: always
     expire_in: 1 week