fix: remove homebrew install information (not working) (#382)

Signed-off-by: Chapman Pendery <cpendery@vt.edu>

Author: cpendery

Formula/inshellisense.rb

@@ -8,17 +8,11 @@
 
 ### Installation
 
-**npm (recommended)**
+**npm**
 ```shell
 npm install -g @microsoft/inshellisense
 is init
 ```
-**homebrew (macOS/linux)**
-```shell
-brew tap microsoft/inshellisense https://github.com/microsoft/inshellisense
-brew install inshellisense
-is init
-```
 
 ### Updating