[ubuntu] Rename build scripts (#8866)

* [ubuntu] Rename build scripts

* [ubuntu] Change reboot to inline shell

* [ubuntu] Move disk space validation to pester tests

* [ubuntu] Rename helper and tests files

* [ubuntu] Changes to cleanup, post-deployment and r scripts

images/ubuntu/scripts/build/install-mono.sh

@@ -0,0 +1,28 @@
+#!/bin/bash -e
+################################################################################
+##  File:  install-mono.sh
+##  Desc:  Install Mono
+################################################################################
+
+source $HELPER_SCRIPTS/os.sh
+
+LSB_CODENAME=$(lsb_release -cs)
+
+# There are no packages for Ubuntu 22 in the repo, but developers confirmed that packages from Ubuntu 20 should work
+if isUbuntu22; then
+    LSB_CODENAME="focal"
+fi
+
+# Test to see if the software in question is already installed, if not install it
+# wget "http://keyserver.ubuntu.com/pks/lookup?op=get&search=0x3FA7E0328081BFF6A14DA29AA6A19B38D3D831EF" -O out && sudo apt-key add out && rm out
+
+apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys 3FA7E0328081BFF6A14DA29AA6A19B38D3D831EF
+echo "deb https://download.mono-project.com/repo/ubuntu stable-$LSB_CODENAME main" | tee /etc/apt/sources.list.d/mono-official-stable.list
+apt-get update
+apt-get install -y --no-install-recommends apt-transport-https mono-complete nuget
+
+rm /etc/apt/sources.list.d/mono-official-stable.list
+rm -f /etc/apt/sources.list.d/mono-official-stable.list.save
+echo "mono https://download.mono-project.com/repo/ubuntu stable-$LSB_CODENAME main" >> $HELPER_SCRIPTS/apt-sources.txt
+
+invoke_tests "Tools" "Mono"