CI setup for Update of BASOP code from float repo

Envisioned setup for updating the BASOP code to the latest floating point code version:

• work happens on parallel branches main-pc (branched off from main) and float-pc (branched off from ivas-float-update)
  • changes are ported via MRs to these two branches
  • CI pipeline for these MRs should be equivalent to the CI setup in the floating point repository
• 1. To be done before porting starts - Minimal CI setup from ivas-codec repo
  • build stage
  • basic BE tests: ivas-pytest-on-merge-request, renderer-pytest-on-merge-request -> !908 (merged)
  • comparison should be done to the respective parent branch (main for main-pc, ivas-float-update for float-pc)
  • validation jobs: branch-is-up-to-date-with-main-pre and -post (these need to check up-to-date to target branch, not main ⚠️) -> !913 (closed), clang-format-check
• 2. Possible extensions (to be discussed, depends on available computing resources and in some cases on porting order)
  • Treat warnings as errors in build jobs (needs fix + Makefile change on float-pc at least)
  • split-rendering-pytest-on-merge-request (together with split rendering port)
  • lc3-wrapper-unit-test
  • codec smoke test, see ivas-codec-pc/ivas-codec#1259
  • renderer smoke test
  • ivas-interop-on-merge-request
  • voip-be-on-merge-request
  • check-bitexactness-hrtf-rom-and-file
  • check-bitexactness-ext-and-transport-format (needs EXT implementation for all formats to be ported first)
  • be-2-evs-windows and be-2-evs-linux (maybe not port from float, but rather use the variant that exists in this repo)
  • check-first-frame-is-sid
  • pytest-compare-20ms-and-5ms-rendering
• 3. What else?
  • sanitizer tests with short testvectors (depends on runtime, especially for the main-pc branch, where BASOP code is run) -> !982 (merged)
• Leftovers/notes:
  • check for warnings is disabled in build job with sanitizers (clang)