Remove ICU from the toolchain

[jmschonfeld]

Now that Foundation builds against its own swift-foundation-icu repo, we no longer need to build the upstream libicu repo for the toolchain. This removes the libicu build from the toolchain

[jmschonfeld]

@swift-ci please smoke test

[compnerd]

Probably a good idea to do a toolchain build on this.

[compnerd]

@swift-ci please build toolchain

[finagolfin]

Oh nice, but I see some docs that still refer to this libicu checkout, maybe those should be removed too?

[jmschonfeld]

Oh nice, but I see some docs that still refer to this libicu checkout, maybe those should be removed too?

I think the first two files are just quite old and out of date in general - I see lots of details in each file unrelated to ICU that are incorrect or no longer the case at this point. I think that those could definitely use an update, but they should probably be updated wholesale rather than just this piece so I think it might be best to save that for a future PR. The final one seems like it could make sense to remove the part related to ICU (but leave the LFS comment in place in case it applies to other repos). I can update that once the toolchain builds pass so they can finish before adding a commit if we want to remove that comment from the document

[AnthonyLatsis]

The final one seems like it could make sense to remove the part related to ICU (but leave the LFS comment in place in case it applies to other repos)

That item is ICU-specific, so please remove it entirely. Thanks!

[jmschonfeld]

@compnerd it looks like all of the full toolchain builds passed 👍🏻

[jmschonfeld]

@swift-ci please smoke test

[compnerd]

@swift-ci please smoke test Linux platform

[jmschonfeld]

@swift-ci please smoke test Linux platform

[jmschonfeld]

@swift-ci please clean smoke test Linux platform

[jmschonfeld]

@swift-ci please clean smoke test Linux platform

[jmschonfeld]

@swift-ci please clean smoke test Linux platform