CI Try caching precompilation

[jumerckx]

I'm not yet sure this does anything. But if this would work, we could split the tests in many more separate jobs.

[giordano]

For what is worth, I personally like expanding lists in the one-per-line format, like in

Reactant.jl/.github/workflows/CI.yml

Lines 67 to 87 in eca8191

	- "1.10"
	- "1.11"
	# - 'nightly'
	os:
	- ubuntu-24.04
	# `ubuntu-22.04-arm` is considered more stable than `ubuntu-24.04-arm`:
	# <https://github.com/orgs/community/discussions/148648#discussioncomment-12099554>.
	- ubuntu-22.04-arm
	# Disable `macOS-13` until
	# <https://github.com/EnzymeAD/Reactant.jl/issues/867> is resolved.
	# - macOS-13
	- macOS-latest
	test_group:
	- core
	- neural_networks
	- integration
	runtime:
	- "PJRT"
	- "IFRT"
	assertions:
	- false

which makes it easy to add remove individual items without messing up with git-blame.

[jumerckx]

Thanks, I'll take this into account.
I'm still mainly messing around with things for now.

Do you think it makes sense to have a cache warmup step with cache keys independent of jobs and testgroup?

[giordano]

If it works, it can make sense.

[jumerckx]

packages are still being precompiled in the test step. I'm looking for a culprit, this seems suspicious:

┌ Warning: Could not use exact versions of packages in manifest, re-resolving
└ @ Pkg.Operations /opt/hostedtoolcache/julia/1.10.10/aarch64/share/julia/stdlib/v1.10/Pkg/src/Operations.jl:1829

[giordano]

You may want to drastically reduce the matrix (ideally to a single element) while you investigate how to make this work, otherwise you'll waste loads of resources and everybody's time.