👷(global) circleci conditional testing

[rlecellier]

Purpose

Use passculture circleci configuration example to skip job unless files have been modified in the right folder.

See: https://github.com/pass-culture/pass-culture-main/blob/9b8c259d683fa4fafa0a0621e83092b09f606927/.circleci/config.yml#L123-L163

We skip the job if no changes are detected on the provided path except if the active branch is the base one or the job is run on a tag

Proposal

• [x] Add a pre-step to check if the job should be run