wip: force nightly build for raspberrypi3-mesa

Maintenance-type: wip

Author: psaavedra

.github/workflows/test-build-nightly.yml

@@ -14,7 +14,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        machine: ['raspberrypi5']
+        machine: ['raspberrypi3-mesa', 'raspberrypi5']
         wpe_vers: ['nightly']
         yocto_rel: ['scarthgap']
     continue-on-error: true
@@ -42,7 +42,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        machine: ['raspberrypi5']
+        machine: ['raspberrypi3-mesa', 'raspberrypi5']
         wpe_vers: ['nightly']
         yocto_rel: ['scarthgap']
     runs-on: [self-hosted, podman]