Merge branch 'en/assert-wo-side-effects'

Merge branch 'en/assert-wo-side-effects'

Ensure what we write in assert() does not have side effects,
and introduce ASSERT() macro to mark those that cannot be
mechanically checked for lack of side effects.

* en/assert-wo-side-effects:
  treewide: replace assert() with ASSERT() in special cases
  ci: add build checking for side-effects in assert() calls
  git-compat-util: introduce ASSERT() macro