ci: Bump upload/download artifact actions to v4

as v3 is being deprecated in a few months

.github/workflows/merge-conflict-auto-label.yml

@@ -1,19 +0,0 @@
-name: Merge Conflict Auto Label
-on:
-  workflow_dispatch: # Manual run
-  push:
-    branches:
-      - main
-  schedule:
-    - cron: "10 21 * * *" # Runs at 21:10; time was chosen based on contributor activity and low GitHub Actions cron load.
-
-jobs:
-  triage:
-    runs-on: ubuntu-latest
-    steps:
-      - uses: mschilde/auto-label-merge-conflicts@master
-        with:
-          CONFLICT_LABEL_NAME: "merge conflicts"
-          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-          MAX_RETRIES: 5
-          WAIT_MS: 5000

.github/workflows/release.yml

@@ -34,7 +34,7 @@ jobs:
           wget "https://github.com/R2Northstar/NorthstarLauncher/releases/download/${{ env.NORTHSTAR_VERSION }}/northstar-launcher.zip"
       - name: Download DiscordRPC plugin
         run:
-          wget "https://github.com/R2Northstar/NorthstarDiscordRPC/releases/download/v10/northstar-discord-rpc.zip"
+          wget "https://github.com/R2Northstar/NorthstarDiscordRPC/releases/download/v9/northstar-discord-rpc.zip"
       - name: Download compiled stubs
         run:
           wget "https://github.com/R2Northstar/NorthstarStubs/releases/download/v1/NorthstarStubs.zip"
@@ -100,7 +100,7 @@ jobs:
           sha512sum Northstar.release.${{ env.NORTHSTAR_VERSION }}.zip >> $GITHUB_STEP_SUMMARY
           echo "\`\`\`" >> $GITHUB_STEP_SUMMARY
       - name: Upload zip to release draft
-        uses: softprops/action-gh-release@v2
+        uses: softprops/action-gh-release@v1
         if: startsWith(github.ref, 'refs/tags/v') && !contains(env.NORTHSTAR_VERSION, '-rc')
         with:
           draft: true