Do not ship Angular build cache in release tarballs

[Galen Charlton]

As of Angular v13, its build cache is now persistent by default. That cache lives in Open-ILS/src/eg2/.angular/cache, but is needed only when (re)building the Angular app. Consequently, it does not need to be included in the release tarballs, and excluding it will save a significant amount of space.

[Galen Charlton (gmc)]

Patch is available in the working branch user/gmcharlt/lp2048907_exclude_angular_build_cache_from_tarball / https://git.evergreen-ils.org/?p=working/Evergreen.git;a=shortlog;h=refs/heads/user/gmcharlt/lp2048907_exclude_angular_build_cache_from_tarball

[Jane Sandberg (sandbergja)]

Good catch, Galen! Thanks for this patch.

I tried creating simple tarballs with `build/tools/make_release -i -n -x -v 3.12.1 -F 3.12.0 -f origin/tags/rel_3_12_0 -c`. Without this patch, the tarball was 124 GB! With the patch, it's only 85 GB.

I went through the installation steps (https://evergreen-ils.org/documentation/install/README_3_12.html) using the tarball I made with this patch. The angular client still worked just fine.

Pushed to rel_3_11 and above.