chore(ci): cache Vagrant boxes with Github Actions Cache

[jheidbrink]

Summary

The Github Actions workflows see a lot of HTTP 429 when downloading Vagrant boxes from the Vagrant Cloud.

As a quick fix, simply cache the ~/.vagrant.d/boxes directory using the actions/cache action.

Test Plan

Spin up the magma_dev, magma_test and magma_trfserver VMs and verify the cache is used: https://github.com/jheidbrink/magma/actions/runs/2507266285

Additional Information

• This change is backwards-breaking

All our boxes (lte, cwf) currently use around 8 GiB of disk space. That is close to the cache size limit of 10GiB. Given that we don't use the Github Actions caches elsewhere and don't regularly update the boxes, this should be ok for now. Once the boxes receive more regular upgrades, we need to find a more elaborate solution.

[github-actions]

Thanks for opening a PR! 💯

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Howto

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More info

Please take a moment to read through the Magma project's

• Contributing Conventions for norms around contributed code

If this is your first Magma PR, also consider reading

• Developer Onboarding for onboarding as a new Magma developer
• Development Workflow for guidance on your first pull request
• CI Checks for points of contact for failing or flaky CI checks
• GitHub-to-Slack mappings for Magma maintainers for guidance on how to contact maintainers on Slack

[nstng]

lgtm - discussed offline

[github-actions]

dp-workflow

18 tests   18 ✔️  4m 54s ⏱️
  2 suites    0 💤
  2 files      0 ❌

Results for commit b54aad3.