[CI]: flaky: Install Build JAR for Robolectric Testing: x86_64-unknown-linux-gnu `No such file or directory`

[david-allison]

Seen this twice, flaky

/private/tmp/d20210526-2040-11epx9s/x86_64-unknown-linux-gnu/./x86_64-unknown-linux-gnu/lib: No such file or directory

Run brew tap SergioBenitez/osxct
==> Tapping sergiobenitez/osxct
Cloning into '/usr/local/Homebrew/Library/Taps/sergiobenitez/homebrew-osxct'...
Tapped 3 formulae (31 files, 37.7KB).
==> Installing x86_64-unknown-linux-gnu from sergiobenitez/osxct
==> Downloading https://github.com/SergioBenitez/homebrew-osxct/releases/download/x86_64-unknown-linux-gnu/x86_64-unknown-linux-gnu.tar.gz
==> Downloading from https://github-releases.githubusercontent.com/51188631/5f9f7a98-e85d-11e7-89fe-bc86e5f4edc9?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=AKIAIWNJYAX4CSVEH53A%2F20210526%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Date=20210526T220607Z&X-Amz-Expires=300&X-Amz-Signature=c30b1e451e71c564cb92db872dd1db4dc96cbc806f27ed20d1103174c3df3187&X-Amz-SignedHeaders=host&actor_id=0&key_id=0&repo_id=51188631&response-content-disposition=attachment%3B%20filename%3Dx86_64-unknown-linux-gnu.tar.gz&response-content-type=application%2Foctet-stream
cp: /private/tmp/d20210526-2040-11epx9s/x86_64-unknown-linux-gnu/./x86_64-unknown-linux-gnu/lib: unable to copy extended attributes to /private/tmp/x86_64-unknown-linux-gnu-20210526-2040-iyzso7/x86_64-unknown-linux-gnu/x86_64-unknown-linux-gnu/lib: No such file or directory
cp: /private/tmp/d20210526-2040-11epx9s/x86_64-unknown-linux-gnu/./x86_64-unknown-linux-gnu/lib: No such file or directory
Error: Failure while executing; `cp -pR /private/tmp/d20210526-2040-11epx9s/x86_64-unknown-linux-gnu/. /private/tmp/x86_64-unknown-linux-gnu-20210526-2040-iyzso7/x86_64-unknown-linux-gnu` exited with 1. Here's the output:
cp: /private/tmp/d20210526-2040-11epx9s/x86_64-unknown-linux-gnu/./x86_64-unknown-linux-gnu/lib: unable to copy extended attributes to /private/tmp/x86_64-unknown-linux-gnu-20210526-2040-iyzso7/x86_64-unknown-linux-gnu/x86_64-unknown-linux-gnu/lib: No such file or directory
cp: /private/tmp/d20210526-2040-11epx9s/x86_64-unknown-linux-gnu/./x86_64-unknown-linux-gnu/lib: No such file or directory
Error: Process completed with exit code 1.