Resolve "Optimize CI pipeline"

This MR optimizes the CI pipelines by doing the following:

• Enable out-of-order execution of jobs using the needs clause
• Split tests for better parallelization
  • Evaluate the parallel keyword
  • Evaluate the interruptible keyword
• Reduce artifact size by removing unneeded object files between stages
• Refactor Docker images and make them versioned
  • Create a gekkofs/core image for system dependencies
  • Create a gekkofs/deps image for downloaded dependencies
  • Create a gekkofs/linter image for validation of formatting
  • Create a gekkofs/testing image for running tests
  • Create a gekkofs/coverage image to generate coverage reports
  • Add configuration profiles to dl_dep.sh and compile_dep.sh

It also improves the reporting of tests by integrating it with the GitLab UI. This required the following changes:

• Enable JUnit reporting of tests
  • Enable JUnit reporting for integration tests
    • Fix reported filename for GitLab integration
    • Integrate daemon and client logs into JUnit XML
  • Enable JUnit reporting for unit tests

Closes #165 (closed) #157 (closed) #166 (closed) #167 (closed)