Update and pin actions/cache usage to latest 4.x. These were previously
pointing to `@3` which pulls in the latest v3 as they are released, with
the potential to break our workflows if a breaking change or malicious
version on the `@3` stream is ever pushed.
Changing this to a pinned version also means that dependabot will keep
this in the pinned version format (e.g., referencing a SHA) when it
opens a PR to bump the dependency.
The breaking change between v3 and v4 is that v4 requires Node 20 which
should be a non-issue where this is run.
Updates #cleanup
Signed-off-by: Mario Minardi <mario@tailscale.com>
Mario MinardiandGitHub
a8bd0cb9c2