Add try-catch to on_finish section to prevent hang

appveyor.yml

@@ -64,6 +64,7 @@ test_script:
 on_finish: 
   - ps: |
       $ErrorActionPreference = 'Stop'
+      try {
         # Creating project artifact
         $name = git describe
         $zipFilePath = Join-Path $pwd "$name.zip"
@@ -80,3 +81,6 @@ on_finish:
             Write-Host "Pushing package $_ as Appveyor artifact"
             Push-AppveyorArtifact $_
           }
+      } catch {
+        Write-Host -Foreground Red $_
+      }