Image build takes a very long time

Hi, not sure it this an issue or expected - when creating a custom Windows image with the command, the build takes a very long time, over 40 minutes. Just wanted to know if this is normal and if not why this might be taking so long. The command output shows 'Starting Run template...' and then takes about 40 minutes to succeed. Here is my command being run from the Github Actions worflow:
- name: Create VM Image
id: imageBuilder
uses: azure/build-vm-image@v0
with:
location: "eastus"
resource-group-name: "test-group"
managed-identity: "Mission"
vm-size: "Standard_B2s"
source-os-type: "windows"
source-image-type: "platformImage"
source-image: MicrosoftWindowsServer:WindowsServer:2019-Datacenter:latest
customizer-source: "${{ GITHUB.WORKSPACE }}/dist/angular-test-app"
dist-resource-id: "/subscriptions/${{ secrets.SUBSCRIPTION_ID }}/resourceGroups/test-group/providers/Microsoft.Compute/galleries/testGallery/images/testVM"
dist-type: "SharedImageGallery"
dist-location: "eastus"