Merge branch 'ci-add-twine' into 'develop'

install twine

See merge request !1954

.gitlab-ci.yml

@@ -529,6 +529,8 @@ python package:
   stage: release
   variables:
     GIT_STRATEGY: none
+  before_script:
+    - pip install twine
   script: twine upload -u gitlab-ci-token -p ${CI_JOB_TOKEN} --repository-url https://gitlab.mpcdf.mpg.de/api/v4/projects/${CI_PROJECT_ID}/packages/pypi dist/nomad-lab-*.tar.gz
   rules:
     - when: manual
@@ -538,6 +540,8 @@ pypi package:
   stage: release
   variables:
     GIT_STRATEGY: none
+  before_script:
+    - pip install twine
   script: twine upload -u $CI_TWINE_USER -p $CI_TWINE_PASSWORD dist/nomad-lab-*.tar.gz
   rules:
     - if: $CI_COMMIT_TAG