Add Java install step for Homebrew install guide 
Add Java install step for Homebrew install guide 

fix #2438

Closes #2439.

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Reviewed-on: https://github.com/bazelbuild/bazel/pull/2439
PiperOrigin-RevId: 148781010
MOS_MIGRATED_REVID=148781010

bazelbuild/bazel-website,davidzchen/bazel-website,bazelbuild/bazel-website,bazelbuild/bazel-website,davidzchen/bazel-website,davidzchen/bazel-website,davidzchen/bazel-website