add docs on using homebrew tap

While use of the tap is discouraged, there are times that homebrew core doesn't immediately update the formula to the latest version. This provides docs on using the tap to help get the latest released quicker through brew.

Author: danielhelfand

docs/src/docs/usage/install/index.mdx

@@ -53,7 +53,13 @@ brew install golangci-lint
 brew upgrade golangci-lint
 ```
 
-Note: previously we use [tap](https://github.com/golangci/homebrew-tap), but it is obsoleted. We recommend using official formula instead of an obsolete tap.
+Note: Previously we used a [homebrew tap](https://github.com/golangci/homebrew-tap). We recommend using official formula instead of the tap, but sometimes the most recent release 
+isn't immediately available via homebrew core. In this case, the tap formula can be used to install the latest version of `golangci-lint`:
+
+```
+brew tap golangci/tap
+brew install golangci/tap/golangci-lint
+```
 
 It can also be installed through [macports](https://www.macports.org/)
 The macports installation mode is community driven, and not officially maintained by golangci team.