Fix #470

Define env variables $BRANCH and $CYPRESS_RETRIES

Source: https://graysonkoonce.com/getting-the-current-branch-name-during-a-pull-request-in-travis-ci/

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Cypress is looking for a env var by default. See: https://docs.cypress.io/guides/guides/command-line.html#cypress-run

So I guess, all what we have to do is to give the env var another name.
I also added a measure to avoid running out of quota: Disable recording
if dependabot just updates dependencies.

.travis.yml

@@ -21,6 +21,9 @@ install:
   - wait-on http://localhost:7474
 
 script:
+  - export CYPRESS_RETRIES=1
+  - export BRANCH=$(if [ "$TRAVIS_PULL_REQUEST" == "false" ]; then echo $TRAVIS_BRANCH; else echo $TRAVIS_PULL_REQUEST_BRANCH; fi)
+  - echo "TRAVIS_BRANCH=$TRAVIS_BRANCH, PR=$PR, BRANCH=$BRANCH"
   # Backend
   - docker-compose exec backend yarn run lint
   - docker-compose exec backend yarn run test:jest --ci --verbose=false --coverage
@@ -34,7 +37,10 @@ script:
   - docker-compose exec webapp yarn run test --ci --verbose=false --coverage
   - docker-compose exec -d backend yarn run test:before:seeder
   # Fullstack
-  - CYPRESS_RETRIES=1 yarn run cypress:run
+  # Disable recording cypress tests if we just update dependencies. This is to
+  # avoid running out of quota.
+  - if [[ $BRANCH == *"dependabot"* ]]; then unset CYPRESS_RECORD_KEY ; fi
+  - yarn run cypress:run
   # Coverage
   - codecov