Change Linux SDK tarball extension to reflect LunarG website (#265)

* Update install_dependencies_linux.sh

Installation instructions referred to the VulkanSDK Linux tarball as a tar.gz, but on the lunarg website it is provided as a tar.xz.
Changed the command to reflect that.

* Update 02_Development_environment.adoc

Linux installation instructions referred to the VulkanSDK Linux tarball as a .tgz, but on the lunarg website it is provided as a tar.xz.
Changed the command to reflect that.

Author: ricardosetton

en/02_Development_environment.adoc

@@ -317,7 +317,7 @@ link to the latest on like so:
 [,shell]
 ----
 pushd vulkansdk
-tar -xzf vulkansdk-linux-x86_64-1.4.304.1.tgz
+tar -xf vulkansdk-linux-x86_64-1.4.304.1.tar.xz
 ln -s 1.4.304.1 default
 ----
 

scripts/install_dependencies_linux.sh

@@ -121,7 +121,7 @@ echo "Now you need to install the Vulkan SDK:"
 echo "1. Download the tarball from https://vulkan.lunarg.com/"
 echo "2. Extract it to a convenient location, for example:"
 echo "   mkdir -p ~/vulkansdk"
-echo "   tar -xzf vulkansdk-linux-x86_64-<version>.tar.gz -C ~/vulkansdk"
+echo "   tar -xf vulkansdk-linux-x86_64-<version>.tar.xz -C ~/vulkansdk"
 echo "   cd ~/vulkansdk"
 echo "   ln -s <version> default"
 echo ""