Repack the distribution on CI

To avoid GitHub packing it again (see
actions/upload-artifact#39).

.github/workflows/ci.yml

@@ -70,12 +70,16 @@ jobs:
         run: |
           $version = ./scripts/Get-Version.ps1
           Write-Output "::set-env name=AVALONIA_RIDER_VERSION::$version"
+      - name: Unpack Distribution # for the purpose of uploading
+        if: matrix.image == 'ubuntu-18.04'
+        shell: pwsh
+        run: scripts/Unpack-Distribution.ps1
       - name: Upload Distribution
         if: matrix.image == 'ubuntu-18.04'
         uses: actions/upload-artifact@v2
         with:
           name: avaloniarider-${{ env.AVALONIA_RIDER_VERSION }}
-          path: build/distributions/avaloniarider-${{ env.AVALONIA_RIDER_VERSION }}.zip
+          path: build/distributions/unpacked
 
       # Finalize
       - name: Stop Gradle Daemon # to collect Gradle cache

scripts/Unpack-Distribution.ps1

@@ -0,0 +1,21 @@
+<#
+    .SYNOPSIS
+        The purpose of this script is to unpack the compressed plugin artifact.
+
+        It is used during CI builds to generate the layout for uploading.
+    .PARAMETER DistributionsLocation
+        Path to the directory containing compressed plugin distribution.
+#>
+param (
+    [string] $DistributionsLocation = "$PSScriptRoot/../build/distributions"
+)
+
+$file = Get-Item $DistributionsLocation/*
+if (!$file) {
+    throw "File not found in $DistributionsLocation"
+}
+if ($file.Count -gt 1) {
+    throw "Found more files than expected in ${DistributionsLocation}: $($file.Count)"
+}
+
+Expand-Archive -Path $file -DestinationPath $DistributionsLocation/unpacked