(GH-3572) Only build TargetFrameworks netcoreapp3.1, net5.0 & net6.0

* fixes #3572

.github/workflows/build.yml

@@ -21,11 +21,6 @@ jobs:
       - name: Fetch all history for all tags and branches
         run: git fetch --prune --unshallow
 
-      - name: Install .NET Core SDK 2.1.x
-        uses: actions/setup-dotnet@v1
-        with:
-          dotnet-version: '2.1.x'
-
       - name: Install .NET Core SDK 3.1.x
         uses: actions/setup-dotnet@v1
         with:
@@ -42,9 +37,7 @@ jobs:
             include-prerelease: 'true'
 
       - name: Run Cake script
-        uses: cake-build/cake-action@v1
-        env:
-          DOTNET_ROLL_FORWARD_ON_NO_CANDIDATE_FX: 2
+        uses: cake-build/cake-action@master
         with:
           target: Run-Integration-Tests
-          cake-bootstrap: true
+          cake-version: tool-manifest

README.md

@@ -17,7 +17,6 @@ Cake (C# Make) is a build automation system with a C# DSL to do things like comp
 | Azure Pipelines             | Centos        | [![Azure Pipelines Cake Centos status](https://dev.azure.com/cake-build/Cake/_apis/build/status/Azure%20Pipelines%20-%20Build%20Cake%20Centos%207?&branchName=develop)](https://dev.azure.com/cake-build/Cake/_build/latest?definitionId=5) | |
 | Azure Pipelines             | Ubuntu        | [![Azure Pipelines Ubuntu Build status](https://dev.azure.com/cake-build/Cake/_apis/build/status/Azure%20Pipelines%20-%20Build%20Cake%20Ubuntu?&branchName=develop)](https://dev.azure.com/cake-build/Cake/_build/latest?definitionId=3) | |
 | AppVeyor                    | Windows       | [![AppVeyor branch](https://img.shields.io/appveyor/ci/cakebuild/cake/develop.svg)](https://ci.appveyor.com/project/cakebuild/cake/branch/develop)                  | [![AppVeyor branch](https://img.shields.io/appveyor/ci/cakebuild/cake-eijwj/develop.svg)](https://ci.appveyor.com/project/cakebuild/cake-eijwj)  |
-| Travis                      | Ubuntu / MacOS | [![Travis build status](https://travis-ci.org/cake-build/cake.svg?branch=develop)](https://travis-ci.org/cake-build/cake)                                           |                                                                                                                                                                     |
 | TeamCity                    | Windows       | [![TeamCity Build Status](http://img.shields.io/teamcity/codebetter/Cake_CakeMaster.svg)](http://teamcity.codebetter.com/viewType.html?buildTypeId=Cake_CakeMaster) |                                                                                                                                                                     |
 | Bitrise                     | MacOS         | [![Build Status](https://app.bitrise.io/app/42eaef77e8db4a5c/status.svg?token=EDjHGK5njNJ-MrhSbvKM1w&branch=develop)](https://app.bitrise.io/app/42eaef77e8db4a5c)  | ![Build Status](https://app.bitrise.io/app/804b431c1f27e0a0/status.svg?token=qKosHEaJAJEqzZcq4s5WRg&branch=develop)                                                        |
 | Bitrise                     | Debian         | [![Build Status](https://app.bitrise.io/app/ea0c6b3c61eb1e79/status.svg?token=KJqOWXllYXz3WYqcB861Uw&branch=develop)](https://app.bitrise.io/app/ea0c6b3c61eb1e79)  | ![Build Status](https://app.bitrise.io/app/5a406f34f22113c6/status.svg?token=TQPbsmA9yP-iJOhzunIP4w&branch=develop)                                                        |

appveyor.yml

@@ -7,7 +7,6 @@ init:
 build_script:
   - ps: Invoke-RestMethod -Uri 'https://dot.net/v1/dotnet-install.ps1' -OutFile '.\dotnet-install.ps1'
   - ps: New-Item -Path .\.dotnet -ItemType Directory -Force | Out-Null
-  - ps: .\dotnet-install.ps1 -Channel 2.1 -InstallDir .\.dotnet
   - ps: .\dotnet-install.ps1 -Channel 3.1 -InstallDir .\.dotnet
   - ps: .\dotnet-install.ps1 -Channel 5.0 -InstallDir .\.dotnet
   - ps: .\build.ps1 --target="AppVeyor"