Remove Google SDK instructions. (#28165)

* Remove Google SDK instructions.

Ref: https://github.com/kubernetes/website/issues/20232

* Remove Google SDK instructions for MacOS

* Remove Google SDK instructions for Windows

* Delete install-kubectl-gcloud.md

content/en/docs/tasks/tools/install-kubectl-windows.md

@@ -21,7 +21,6 @@ The following methods exist for installing kubectl on Windows:
 
 - [Install kubectl binary with curl on Windows](#install-kubectl-binary-with-curl-on-windows)
 - [Install on Windows using Chocolatey or Scoop](#install-on-windows-using-chocolatey-or-scoop)
-- [Install on Windows as part of the Google Cloud SDK](#install-on-windows-as-part-of-the-google-cloud-sdk)
 
 
 ### Install kubectl binary with curl on Windows
@@ -127,10 +126,6 @@ If you have installed Docker Desktop before, you may need to place your `PATH` e
 Edit the config file with a text editor of your choice, such as Notepad.
 {{< /note >}}
 
-### Install on Windows as part of the Google Cloud SDK
-
-{{< include "included/install-kubectl-gcloud.md" >}}
-
 ## Verify kubectl configuration
 
 {{< include "included/verify-kubectl.md" >}}
@@ -147,4 +142,4 @@ Below are the procedures to set up autocompletion for Zsh, if you are running th
 
 ## {{% heading "whatsnext" %}}
 
-{{< include "included/kubectl-whats-next.md" >}}
+{{< include "included/kubectl-whats-next.md" >}}