GitHub Actions: Try out node_modules caching

[SleeplessByte]

https://docs.github.com/en/free-pro-team@latest/actions/guides/caching-dependencies-to-speed-up-workflows

Node modules don't really take a lot of time in the proposed actions #875 , but we should still benchmark if these help.

[abhishekkhanna2710]

hey , Can you assign me this issue?

[harshkr70046]

hey , Can you assign me this issue?

[SleeplessByte]

Sorry, this was already implemented. See https://github.com/exercism/javascript/actions/runs/12843544401/job/35815605474