Fix missing gnupg package issue during installing k8s gpg file process (

sonic-net#18158)

### Why I did it
When try to install k8s gpg file, there reports an error.
- "E: gnupg, gnupg2 and gnupg1 do not seem to be installed, but one of them is required for this operation   curl: (23) Failed writing body". 

To fix error we need to install gunpg package. But apt-key add is going to be deprecated, mv the gpg file to /etc/apt/trusted.gpg.d/ directly
### How I did it
Download k8s gpg file and put it in /etc/apt/trusted.gpg.d/
#### How to verify it
We can install k8s gpg file successfully, but no gnupg package installed inside sonic image.

build_debian.sh

@@ -273,7 +273,7 @@ install_kubernetes () {
     local ver="$1"
     sudo https_proxy=$https_proxy LANG=C chroot $FILESYSTEM_ROOT curl -fsSL \
         https://packages.cloud.google.com/apt/doc/apt-key.gpg | \
-        sudo LANG=C chroot $FILESYSTEM_ROOT apt-key add -
+        sudo LANG=C chroot $FILESYSTEM_ROOT tee /etc/apt/trusted.gpg.d/kubernetes.asc
     ## Check out the sources list update matches current Debian version
     sudo cp files/image_config/kubernetes/kubernetes.list $FILESYSTEM_ROOT/etc/apt/sources.list.d/
     sudo LANG=C chroot $FILESYSTEM_ROOT apt-get update