Delete job transfer workflow artifact

The "Arduino IDE" GitHub Actions workflow uses a workflow artifact to transfer the build artifacts between jobs. Now that
separate tester build artifacts are produced, the monolithic job transfer artifact is superfluous once the workflow run
is finished. Deleting it avoids potential confusion for beta testers and unnecessary storage space usage.

Author: per1234

Diff for: .github/workflows/build.yml

@@ -85,6 +85,39 @@ jobs:
           name: ${{ env.JOB_TRANSFER_ARTIFACT }}
           path: electron/build/dist/build-artifacts/
 
+  artifacts:
+    name: ${{ matrix.artifact.name }} artifact
+    needs: build
+    if: always() && needs.build.result != 'skipped'
+    runs-on: ubuntu-latest
+
+    strategy:
+      matrix:
+        artifact:
+          - path: "*Linux_64bit.zip"
+            name: Linux_X86-64
+          - path: "*macOS_64bit.dmg"
+            name: macOS
+          - path: "*Windows_64bit.exe"
+            name: Windows_X86-64_interactive_installer
+          - path: "*Windows_64bit.msi"
+            name: Windows_X86-64_MSI
+          - path: "*Windows_64bit.zip"
+            name: Windows_X86-64_zip
+
+    steps:
+      - name: Download job transfer artifact
+        uses: actions/download-artifact@v2
+        with:
+          name: ${{ env.JOB_TRANSFER_ARTIFACT }}
+          path: ${{ env.JOB_TRANSFER_ARTIFACT }}
+      
+      - name: Upload tester build artifact
+        uses: actions/upload-artifact@v2
+        with:
+          name: ${{ matrix.artifact.name }}
+          path: ${{ env.JOB_TRANSFER_ARTIFACT }}/${{ matrix.artifact.path }}
+
   changelog:
     needs: build
     runs-on: ubuntu-latest
@@ -184,35 +217,18 @@ jobs:
           AWS_ACCESS_KEY_ID: ${{ secrets.AWS_ACCESS_KEY_ID }}
           AWS_SECRET_ACCESS_KEY: ${{ secrets.AWS_SECRET_ACCESS_KEY }}
 
-  artifacts:
-    name: ${{ matrix.artifact.name }} artifact
-    needs: build
+  clean:
+    # This job must run after all jobs that use the transfer artifact.
+    needs:
+      - build
+      - publish
+      - release
+      - artifacts
     if: always() && needs.build.result != 'skipped'
     runs-on: ubuntu-latest
 
-    strategy:
-      matrix:
-        artifact:
-          - path: "*Linux_64bit.zip"
-            name: Linux_X86-64
-          - path: "*macOS_64bit.dmg"
-            name: macOS
-          - path: "*Windows_64bit.exe"
-            name: Windows_X86-64_interactive_installer
-          - path: "*Windows_64bit.msi"
-            name: Windows_X86-64_MSI
-          - path: "*Windows_64bit.zip"
-            name: Windows_X86-64_zip
-
     steps:
-      - name: Download job transfer artifact
-        uses: actions/download-artifact@v2
+      - name: Remove unneeded job transfer artifact
+        uses: geekyeggo/delete-artifact@v1
         with:
           name: ${{ env.JOB_TRANSFER_ARTIFACT }}
-          path: ${{ env.JOB_TRANSFER_ARTIFACT }}
-      
-      - name: Upload tester build artifact
-        uses: actions/upload-artifact@v2
-        with:
-          name: ${{ matrix.artifact.name }}
-          path: ${{ env.JOB_TRANSFER_ARTIFACT }}/${{ matrix.artifact.path }}