DX-5120: Parallel execution of BLT artifact:deploy conflicts due to use of fixed /tmp-blt-deploy/ dir name

[jcnventura]

Describe the bug
BLT provides a very useful tool to automate the process of building and deploying an artifact to Acquia. We currently use blt artifact-deploy with this purpose in our CI pipelines.

The problem is that artifact:deploy uses /tmp/blt-deploy/ to create the artifact, which can lead to problems running the CI pipeline for multiple projects using BLT.

To Reproduce
Steps to reproduce the behavior, ideally starting from a fresh install of BLT:

1. Run blt artifact-deploy
2. Check that the repo of the project is checked out to /tmp/blt-deploy/
3. Run blt artifact-deploy in parallel for a second project
4. Check that the 2nd run started to delete the files for the 1st project in /tmp/blt-deploy/

Expected behavior
I expect that BLT will be able to use a temporary name as returned by PHP's tempnam() function.

System information

• Operating system type: Linux CentOS
• Operating system version: 7.9.2009
• BLT version: 13.0.1.0

Additional context
We currently use GitLab CI to run the CI pipelines.