Add option to cache SPM packages

[rizwankce]

What it Does

• Closes IMPROVE - Build time for docc generation with Github Action #81
• To make a documentation CI job run faster by caching the derived data folder along with build folder

How I Tested

• Tested on my fork repo. Please check the link for the difference

Notes

• Caching was able to save some time for the each build. For the first time since there is no cache it will run on usual time but from the second time onwards it will be little faster.
• first run without cache takes 7m 31s and second run with cache takes 5m 16s

Screenshot

[rizwankce]

@mikaelacaron This PR tackles the speediness of the CI job. We don't get consistent data from the GitHub runners - but we do get 3min savings from the SPM caching.

[mikaelacaron]

Is there ever going to be a need to delete the cache? Should we make a manual action, for if that is ever needed?

[rizwankce]

@mikaelacaron

We don't need to delete the cache. It's automatically done on every job. However for stored cache can be deleted from GitHub UI.

Do we need to delete it in any circumstance?

[mikaelacaron]

However for stored cache can be deleted from GitHub UI.
How do I do that?

I'm guessing if there's ever an issue with the CI, at some point we'd want to be able to delete the cache as a first troubleshooting step?

[mikaelacaron]

@rizwankce I don't think the cache has made a difference for me, it's still taking 6-7 minutes to run the deploy documentation job

[rizwankce]

@mikaelacaron it will work only on second time onwards. However I will check on this ropo GitHub actions.

[mikaelacaron]

No worries at all, I'm letting you know, so far, I haven't seen any impact.

[rizwankce]

Just take a look at it. Time saving is not as significant as I saw before on my repo.

I'm gonna take another look at it. I'll send a PR if I found better solution.

[mikaelacaron]

sounds good! it's not critical so it's fine if you want to move onto different issues!

[rizwankce]

@mikaelacaron its seems the performance of the CI machines is not consistent. Now I see 4 mins job on this repo. In that only 2 mins for building the doc. It could be based on the Github Free plan. Im not sure.

So I will move with other issues.