Variable Expressions not correctly evaluated when using Windows variable syntax

Summary

When using only in a job with variables the Windows variable syntax (e.g. $env:VAR or %VAR%) seems not to be evaluated correctly. The CI Lint always throws an error (actually two different errors depending on the syntax).

The errors are either:

• Error: jobs:JOB_NAME:only variables invalid expression syntax
• Error: (): did not find expected '-' indicator while parsing a block collection at line LINE column COLUMN

If I am doing something wrong here, I simply can't figure it out.

EDIT: Contrary to the documentation on variables on different systems, the Linux variable syntax seems to work perfectly even on a Windows runner.

Steps to reproduce

Fail in CI LINT

Error: (): did not find expected '-' indicator while parsing a block collection at line 9 column 7

stages:
  - build
build_job:
  stage: build
  only:
    refs:
      - pipelines
    variables:
      - "release" == %CI_COMMIT_REF_SLUG%
  script:
    - echo something

Error: jobs:build_job:only variables invalid expression syntax

stages:
  - build
build_job:
  stage: build
  only:
    refs:
      - pipelines
    variables:
      - '"release" == %CI_COMMIT_REF_SLUG%'
  script:
    - echo something

It does not matter what comes first here, the variable or the string and switching quotes (double single) neither

Working in CI LINT

stages:
  - build
build_job:
  stage: build
  only:
    refs:
      - pipelines
    variables:
      - $CI_COMMIT_REF_SLUG == "release"
  script:
    - echo something

What is the current bug behavior?

CI Lint throws an error on out local EE Instance as well as on gitlab.com

What is the expected correct behavior?

Should be considered correct

Relevant logs and/or screenshots