Update CI following conda/conda (#452)

* bring upstream

* Update Upstream Tests workflow

* Modernize CI based on conda/conda

* Integrate all tests in a single workflow

* use win env var syntax

* it's powershell

* install miniforge

* py312 does not have conda-build

* report failures

* readd canaries

* Install both packages in editable mode

* use conda-build rc temporarily

* force color

* use python -m pytest

* conda-libmamba-solver works ok with no splits

* install conda only for conda-libmamba-solver tests

* initialize and source

* switch label/dev

* only source

* it's under shell

* do init for conda-lock?

* switch to CMD?

* use || exit 1?

* force an error to test CI

* revert

* rename

* missing if

* debug

* use a different dependency

* revert

* annotate more changes, disable codecov

* move rerun-failures to workflow only

* debug windows

* update path filter

* simplify test_conda_lock

* do not use miniforge here

* re-enable full workflow

* remove tmate and --sw

* remove unneeded steps

* print durations