workflows: test build all supported boards on push and merge

We were previously testing for only the aludel_mini but building for all
boards on every PR will help catch digressions sooner.

Signed-off-by: Mike Szczys <[email protected]>

Author: szczys

.github/workflows/test.yml

@@ -7,9 +7,22 @@ on:
   pull_request:
 
   push:
+    branches: [ main ]
 
 jobs:
-  test_build:
+  test_build_nrf9160dk:
+    uses: ./.github/workflows/build_zephyr.yml
+    with:
+      ZEPHYR_SDK: 0.16.3
+      BOARD: nrf9160dk/nrf9160/ns
+      ARTIFACT: false
+  test_build_aludel_elixir:
+    uses: ./.github/workflows/build_zephyr.yml
+    with:
+      ZEPHYR_SDK: 0.16.3
+      BOARD: aludel_elixir/nrf9160/ns
+      ARTIFACT: false
+  test_build_aludel_mini:
     uses: ./.github/workflows/build_zephyr.yml
     with:
       ZEPHYR_SDK: 0.16.3