Add separate zephyr test job

Author: tannewt

.github/workflows/run-tests.yml

@@ -69,3 +69,28 @@ jobs:
     #   if: matrix.test == 'all'
     #   run: ./run-natmodtests.py extmod/{heapq*,random*,re*}.py
     #   working-directory: tests
+
+  zephyr:
+    runs-on: ubuntu-24.04
+    strategy:
+      fail-fast: false\
+    env:
+      CP_VERSION: ${{ inputs.cp-version }}
+    steps:
+      - name: Set up repository
+        uses: actions/checkout@v4
+        with:
+          submodules: false
+          show-progress: false
+          fetch-depth: 1
+      - name: Set up python
+        uses: actions/setup-python@v5
+        with:
+          python-version: 3.13
+      - name: Set up Zephyr
+        uses: ./.github/actions/deps/ports/zephyr-cp
+      - name: Set up external
+        uses: ./.github/actions/deps/external
+      - name: Run Zephyr build tests
+        if: matrix.test == 'all'
+        run: make -C ports/zephyr-cp test