Changed Xdebug enabling when XDEBUG_ENABLE is not empty rather then not set. Closes 1170.

[AlexSkrypnyk]

Checklist

• Affected Issues have been mentioned in the Closing issues section
• Changelog entry has been written

This PR allows to have XDEBUG_ENABLE: ${XDEBUG_ENABLE:-} in docker-compose.yml and pass XDEBUG_ENABLE value to docker-compose up without changing the contents of docker-compose.yml:

XDEBUG_ENABLE="true" docker-compose up

Please note that in whole codebase in comments it is recommended to use true as a value of XDEBUG_ENABLE, so this change should not have negative effect on existing projects.

Changelog Entry

Change - Xdebug will be enabled only if XDEBUG_ENABLE variable has a value (#1170).

Closing issues

#1170

[AlexSkrypnyk]

@Schnitzel any chance to get this one before v1? The change is minimal, but the DX is greatly improved (no changed docker-compose.yml in git repo when Xdebug was enabled).

[Schnitzel]

@alexdesignworks
yes, sorry. We're a bit behind with reviewing PRs, but my expectation is to get this in before or with 1.0.0