ci: Make build folder available to docker

Author: kirre-bylund

.github/workflows/build-with-image.yml

@@ -53,6 +53,9 @@ jobs:
       - name: Build Plugin with Unreal Automation Tool in image ${{ matrix.UE_IMAGE }}
         continue-on-error: true
         run: |
+          mkdir build
+          chmod 777 build
+          chmod 777 tmp
           docker run --rm -v "$(pwd):/mnt/source" ghcr.io/epicgames/unreal-engine:${{ matrix.UE_IMAGE }} sh -c "/home/ue4/UnrealEngine/Engine/Build/BatchFiles/RunUAT.sh BuildPlugin -TargetPlatforms="Linux" -Plugin="/mnt/source/${SDK_NAME}/${SDK_NAME}.uplugin" -Package="/mnt/source/build" -Rocket -enablecodeanalysis" 2>&1 | tee tmp/logs/UAT.log
           
       - name: Expose log as artifact