macro_with_null_params.yaml:14:3: In project 'sample-project'
    - project:
      ^
macro_with_null_params.yaml:17:9: Defined here
          - sample-job
            ^
macro_with_null_params.yaml:8:3: In job template 'sample-job'
    - job-template:
      ^
macro_with_null_params.yaml:12:9: While expanding builder macro call 'sample-macro'
          - sample-macro:
            ^
macro_with_null_params.yaml:1:3: While expanding builder macro 'sample-macro'
    - builder:
      ^
macro_with_null_params.yaml:6:17: While formatting string 'echo {hello}': Missing parameter: 'hello'
          - shell: 'echo {hello}'
                    ^
