How do I control the execution of pipeline steps by atlassian/trigger-pipeline variables?

[basma_boulekhras]

Hi, 

I would like to control the execution of specific steps in the triggered pipeline by the value of a variable defined in `trigger-pipeline:4.0`. For example, if $TESTS="true" then execute `integration tests` step in my pipeline. If not, skip it. This control if offered based on the branch name to which the code was pushed. Is there a possibility to do the same thing with a variable?

Best regards,