ci: Test with new CI commands to install Octopus CLI

.github/workflows/CI.yml

@@ -10,7 +10,7 @@ concurrency:
 
 jobs:
   generate:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-20.04
 
     steps:
       - uses: actions/checkout@v3
@@ -27,10 +27,7 @@ jobs:
 
       - name: Install Octopus CLI
         run: |
-          sudo apt update && sudo apt install --no-install-recommends gnupg curl ca-certificates apt-transport-https && \
-          curl -sSfL https://apt.octopus.com/public.key | sudo apt-key add - && \
-          sudo sh -c "echo deb https://apt.octopus.com/ stable main > /etc/apt/sources.list.d/octopus.com.list" && \
-          sudo apt update && sudo apt install octopuscli
+          dotnet tool install --global Octopus.DotNet.Cli
 
       - name: Build and package site for publish
         run: |