2021/07/15 macOS Homebrew CI is broken

[traversaro]

Usual period Homebrew/GitHub Actions failure:

2021-07-15T05:52:48.5896070Z �[34m==>�[0m �[1mDownloading https://fastdl.mongodb.org/osx/mongodb-macos-x86_64-5.0.0.tgz�[0m
2021-07-15T05:52:53.6736810Z �[31mError:�[0m The `brew link` step did not complete successfully
2021-07-15T05:52:53.6738060Z The formula built, but is not symlinked into /usr/local
2021-07-15T05:52:53.6745530Z Could not symlink bin/install_compass
2021-07-15T05:52:53.6746530Z Target /usr/local/bin/install_compass
2021-07-15T05:52:53.6748420Z is a symlink belonging to mongodb-community. You can unlink it:
2021-07-15T05:52:53.6750760Z   brew unlink mongodb-community
2021-07-15T05:52:53.6751450Z 
2021-07-15T05:52:53.6752280Z To force the link and overwrite all conflicting files:
2021-07-15T05:52:53.6753990Z   brew link --overwrite mongodb-community
2021-07-15T05:52:53.6754650Z 
2021-07-15T05:52:53.6755360Z To list all files that would be deleted:
2021-07-15T05:52:53.6756970Z   brew link --overwrite --dry-run mongodb-community
2021-07-15T05:52:53.6757700Z 
2021-07-15T05:52:53.6758390Z Possible conflicting files are:
2021-07-15T05:52:53.6761790Z /usr/local/bin/install_compass -> /usr/local/opt/mongodb-community/bin/install_compass
2021-07-15T05:52:53.6765070Z /usr/local/bin/mongo -> /usr/local/opt/mongodb-community/bin/mongo
2021-07-15T05:52:53.6774920Z /usr/local/bin/mongod -> /usr/local/opt/mongodb-community/bin/mongod
2021-07-15T05:52:53.6782920Z /usr/local/bin/mongos -> /usr/local/opt/mongodb-community/bin/mongos

[traversaro]

Appanrently it is a generic Homebrew/GitHub Actions problem: https://github.com/traversaro/github-actions-brew-update-upgrade-check/runs/3075460389 .

[traversaro]

Upstream GitHub Actions issue: actions/runner-images#3733 .

[traversaro]

As the workaround in #827 solves the problem for us, and the root issue is already tracked in actions/runner-images#3733, I think we can close this issue.