Add Homebrew instructions to getting started
Add Homebrew instructions to getting started

This commit adds instructions for installing Elasticsearch via Homebrew
to the Getting Started guide.

Relates #26847

strapdata/elassandra,strapdata/elassandra,strapdata/elassandra,vroyer/elasticassandra,vroyer/elasticassandra,vroyer/elassandra,strapdata/elassandra,strapdata/elassandra,vroyer/elassandra,vroyer/elassandra,vroyer/elasticassandra