Caching should occur even when your job fails

[mcafaro]

The "Post Set up MATLAB" step which uploads MATLAB to the GitHub Actions cache does not appear to run if your job fails. This is unfortunate if MATLAB was set up properly but a subsequent steps happened to fail. It would be nice if even in this case MATLAB were still cached. This often occurs while initially setting up your workflow and having MATLAB cached would decrease the iteration time.

[mcafaro]

One way to do this would be to set post-if: always() in action.yml so that the post script always runs. Then in the main script do something like core.saveState('succeeded', 'true') to communicate to the post script that MATLAB was set up successful. Then in the post script do something like:

const cache = core.getBooleanInput('cache');
const succeeded = core.getState('succeeded');
if (cache && succeeded === 'true') { ...

[mcafaro]

Closed by #148