Nested variable not interpreted in rules:changes gitlab-ci.yml

Summary

Assign a variable to another variable as shown below and use that variable in the rules:changes section in gitlab-ci.yml. I would expect that both job1 and job2 would run in this scenario but it seems that job2 doesn't

Steps to reproduce

Perform any change in the src directory and job2 will not run

Example Project

stages:
    - build

job1:
  image: alpine
  stage: build
  script:
    - echo "job1"
  rules:
    - if: $CI_PIPELINE_SOURCE == "push" || $CI_PIPELINE_SOURCE == "merge_request_event"
      changes:
        - "${project_path}/**/*"
job2:
  image: alpine
  stage: build
  script:
    - echo "job2"
  rules:
    - if: $CI_PIPELINE_SOURCE == "push" || $CI_PIPELINE_SOURCE == "merge_request_event"
      changes:
        - "${project_path_nested}/**/*"

variables:
    project_path: src
    project_path_nested: $project_path

What is the current bug behavior?

job2 is not executed

What is the expected correct behavior?

Both job1 and job2 should be executed

Relevant logs and/or screenshots

Results of GitLab environment info

This issue occurs on GitLab.com (SaaS)

Possible fixes