I have created a scheduled pipeline and I’m injecting the following variable

foo=bar
CANARY_DEPLOY=true 

I have a gitlab-ci.yaml that includes gitlab-ci-common.yaml

# ...
include:
  - project: 'path/devops/gitlab-pipeline'
    ref: master
    file: '/modules/deploy/no-canary.yml'
    rules:
      - if: '$CANARY_DEPLOY == "false"'
  - project: 'path/devops/gitlab-pipeline'
    ref: master
    file: '/modules/deploy/gitlab-ci-common.yml'
    rules:
      - if: '$CANARY_DEPLOY == "true"'

Here’s my gitlab-ci-common.yaml:

deploy_production:
  stage: test
  environment: test
  script:
    - mvn test -Dfoo=$foo

But $foo is not resolving to the passed value, i.e ‘bar’, and instead it is passed as a literal string ‘$foo’. I tried injecting it as -Dfoo=${foo} but no dice.

What could be causing this?