install from source: add support for Jammy Jellyfish

The dotnet team recently added support for installing natively from Jammy feeds on
Ubuntu 22.04:

dotnet/core#7699

This unfortunately created problems with our current install from source
script, as it caused conflicts with
the packages.microsoft.com feed we use in the install from for Debian/Ubuntu.

This change modifies the Debian/Ubuntu dotnet install to install from
Jammy feeds for users on Ubuntu 22.04 and greater while continuing to use
the packages.microsoft.com feed for Debian and older Ubuntu versions.

src/linux/Packaging.Linux/install-from-source.sh

@@ -120,22 +120,39 @@ case "$distribution" in
         $sudo_cmd apt update
         install_shared_packages apt install
 
-        # add dotnet package repository/signing key
-        $sudo_cmd apt update && $sudo_cmd apt install wget -y
-        curl -LO https://packages.microsoft.com/config/"$distribution"/"$version"/packages-microsoft-prod.deb
-        $sudo_cmd dpkg -i packages-microsoft-prod.deb
-        rm packages-microsoft-prod.deb
+        # use packages.microsoft.com feed to install dotnet on Debian or Ubuntu
+        # distros before 22.04 (Jammy Jellyfish). For 22.04 and after, use
+        # native Jammy feeds.
+        isJammyOrGreater=$(dpkg --compare-versions "21.04" "lt" "22.04"; echo $?)
+        useMicrosoftFeed=true
+        if [ $distribution = "ubuntu" ] && [ $isJammyOrGreater -eq 1 ]; then
+                useMicrosoftFeed=false
+        fi
+
+        if $useMicrosoftFeed; then
+            # add dotnet package repository/signing key
+            $sudo_cmd apt update && $sudo_cmd apt install wget -y
+            curl -LO https://packages.microsoft.com/config/"$distribution"/"$version"/packages-microsoft-prod.deb
+            $sudo_cmd dpkg -i packages-microsoft-prod.deb
+            rm packages-microsoft-prod.deb
 
-        # proactively install tzdata to prevent prompts
-        export DEBIAN_FRONTEND=noninteractive
-        $sudo_cmd apt install -y --no-install-recommends tzdata
+            # proactively install tzdata to prevent prompts
+            export DEBIAN_FRONTEND=noninteractive
+            $sudo_cmd apt install -y --no-install-recommends tzdata
+        fi
 
         # install dotnet packages and dependencies if needed
         if [ -z "$(verify_existing_dotnet_installation)" ]; then
             $sudo_cmd apt update
-            $sudo_cmd apt install apt-transport-https -y
-            $sudo_cmd apt update
-            $sudo_cmd apt install dotnet-sdk-6.0 dpkg-dev -y
+            if $useMicrosoftFeed; then
+                # install from packages.microsoft.com
+                $sudo_cmd apt install apt-transport-https -y
+                $sudo_cmd apt update
+                $sudo_cmd apt install dotnet-sdk-6.0 dpkg-dev -y
+            else
+                # install from Jammy
+                $sudo_cmd apt install dotnet6 -y
+            fi
         fi
     ;;
     linuxmint)