[llvm] workflows/release-binaries: Stop using ccache (PR #124415)

[Tom Stellard via llvm-commits]

tstellar wrote:

@carlocab OK, thanks for the documentation links.  So it sounds like the cache is a little more secure than I thought.  

The benefit of using the cache is pretty low.  It's only used for the stage1 builds, which is just a small part of the overall build time.  So, I think it might be best to just not use it for the release binaries.  In general, it's good practice to limit inputs into release artifacts and the cache is just another thing we need to try to secure.

https://github.com/llvm/llvm-project/pull/124415