fix(actions): fix certificatie path

Author: Foxtrot47

.github/workflows/dotnet-winui3.yml

@@ -56,7 +56,7 @@ jobs:
 
     # Create the app package by building and packaging the project
     - name: Create the app package
-      run: msbuild $env:Solution_Name /p:Configuration=$env:Configuration /p:Platform=$env:Platform /p:UapAppxPackageBuildMode=$env:Appx_Package_Build_Mode /p:AppxBundle=$env:Appx_Bundle /p:PackageCertificateKeyFile=GitHubActionsWorkflow.pfx /p:AppxPackageDir="$env:Appx_Package_Dir" /p:GenerateAppxPackageOnBuild=true
+      run: msbuild $env:Solution_Name /p:Configuration=$env:Configuration /p:Platform=$env:Platform /p:UapAppxPackageBuildMode=$env:Appx_Package_Build_Mode /p:AppxBundle=$env:Appx_Bundle /p:PackageCertificateKeyFile=${{ github.workspace }}\GitHubActionsWorkflow.pfx /p:AppxPackageDir="$env:Appx_Package_Dir" /p:GenerateAppxPackageOnBuild=true
       env:
         Appx_Bundle: Never
         Appx_Package_Build_Mode: SideloadOnly