Feat: editorial workflow bitbucket gitlab (#3014)

* refactor: typescript the backends

* feat: support multiple files upload for GitLab and BitBucket

* fix: load entry media files from media folder or UI state

* chore: cleanup log message

* chore: code cleanup

* refactor: typescript the test backend

* refactor: cleanup getEntry unsued variables

* refactor: moved shared backend code to lib util

* chore: rename files to preserve history

* fix: bind readFile method to API classes

* test(e2e): switch to chrome in cypress tests

* refactor: extract common api methods

* refactor: remove most of immutable js usage from backends

* feat(backend-gitlab): initial editorial workflow support

* feat(backend-gitlab): implement missing workflow methods

* chore: fix lint error

* feat(backend-gitlab): support files deletion

* test(e2e): add gitlab cypress tests

* feat(backend-bitbucket): implement missing editorial workflow methods

* test(e2e): add BitBucket backend e2e tests

* build: update node version to 12 on netlify builds

* fix(backend-bitbucket): extract BitBucket avatar url

* test: fix git-gateway AuthenticationPage test

* test(e2e): fix some backend tests

* test(e2e): fix tests

* test(e2e): add git-gateway editorial workflow test

* chore: code cleanup

* test(e2e): revert back to electron

* test(e2e): add non editorial workflow tests

* fix(git-gateway-gitlab): don't call unpublishedEntry in simple workflow

gitlab git-gateway doesn't support editorial workflow APIs yet. This change makes sure not to call them in simple workflow

* refactor(backend-bitbucket): switch to diffstat API instead of raw diff

* chore: fix test

* test(e2e): add more git-gateway tests

* fix: post rebase typescript fixes

* test(e2e): fix tests

* fix: fix parsing of content key and add tests

* refactor: rename test file

* test(unit): add getStatues unit tests

* chore: update cypress

* docs: update beta docs

dev-test/backends/git-gateway/config.yml

@@ -12,7 +12,6 @@ collections:
     folder: content/posts
     create: true
     slug: '{{year}}-{{month}}-{{day}}-{{slug}}'
-    preview_path: 'posts/{{slug}}/index.html'
     fields:
       - label: Template
         name: template
@@ -46,7 +45,6 @@ collections:
     folder: content/pages
     create: true
     slug: '{{slug}}'
-    preview_path: 'pages/{{slug}}/index.html'
     fields:
       - label: Template
         name: template