Convert CI to multi-stage pipelines

Your Environment

• Operating System and version: All CI

Context

Currently, each CI is single stage, completely independent of each other.

Expected Behavior

Splitting CI into stages will allow:

• Better diagnostics: pipeline A failed at stage: build or test
• More free time:
  • sometimes jobs fail formatting, but continue consuming the CI time for build+test. This will be done again after formatting is fixed.
  • tutorials are built in parallel, leading to double compilation of base library
• More flexibility: addition of API/ABI breakage will be easier