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.
The various major versions of `action/upload-artifact` and
`action/download-artifact` are not necessarily compatible.
Align all the uploads / downloads to `v3`.
`v4` exists but is not currently supported on GHES yet.
Etan Kissling
zah
Miran
Nikolay Mitev
Ștefan Talpalaru