Fix: [AzurePipelines] download Windows Dependencies from GitHub Releases

It turns out that Azure Pipelines has a lot of issues downloading
an artifact from your own project if it is triggered from a fork.
From what I could deduce, this is because the API requires a valid
token, which is not set (correctly?) when triggered from a fork.
As it is nicer anyway to publish the Windows Dependencies on GitHub,
it is now published there (and updated at least every week), and
we use the files from GitHub as our dependency.

azure-pipelines-ci.yml

@@ -25,14 +25,13 @@ jobs:
       git config user.name 'OpenTTD CI'
       git rebase origin/master
     displayName: 'Rebase to master'
-  - task: DownloadBuildArtifacts@0
+  - bash: |
+      set -ex
+      curl -L https://github.com/OpenTTD/OpenTTD-CF/releases/download/latest/windows-dependencies.zip > windows-dependencies.zip
+      unzip windows-dependencies.zip
+      rm -f windows-dependencies.zip
     displayName: 'Download dependencies'
-    inputs:
-      buildType: specific
-      project: '8da578ca-c6cf-47b8-b489-d54a7b188de8'
-      pipeline: 2
-      artifactName: 'windows-dependencies'
-      downloadPath: '$(Build.ArtifactStagingDirectory)'
+    workingDirectory: $(Build.ArtifactStagingDirectory)
   - script: $(Build.ArtifactStagingDirectory)\windows-dependencies\vcpkg.exe integrate install
     displayName: 'Install dependencies'
   - task: VSBuild@1