Daily CI uses an outdated Nim 1.6 because it uses `origin/version-1-6`
which is not maintained very regularly. Pull from `upstream/version-1-6`
instead, same as in `ci.yml`, and also make sure that `--mm:refc` is
turned on for `upstream/devel`.
Typically, mixing different versions of GitHub actions may lead to hard
to fix issues. As many libraries have been updated to use actions v4,
also bump our own `actions/checkout@v2`, `actions/checkout@v3`,
`actions/cache@v2` and `actions/cache@v3` to their `@v4` equivalents.
* "official" -> "scenarios", like the submodule
* fewer test binaries - various compile hacks have been improved over
time, test suite should follow
* remove obsolete bls tests - there are better test vectors in
nim-blscurve
* remove obsolete mentions of `ssz_testing`
* remove obsolete comments about proc vs globals, unittest2 already uses
proc's
Etan Kissling
tersec
Miran
Jacek Sieka
Ștefan Talpalaru
Zahary Karadjov