fix(ci): point publish-python-sdk.yml test-sdk at sdk/python Makefile

The previous step ran `cd tests/integration && make test-sdk`, but
tests/integration/Makefile was deleted on 2026-04-24 (commit 6d0a1e3)
during the integration-test reorg. The step has been silently broken
on every Python SDK publish since.

Switch to running sdk/python's own unit-test target (`make install-dev`
+ `make test`), which is what the Node side does for its own SDK.
Integration tests can ride in on a separate workflow when needed.

Author: teovl

.github/workflows/publish-python-sdk.yml

@@ -30,13 +30,16 @@ jobs:
       - name: Checkout repository
         uses: actions/checkout@v4
 
-      - name: Set up Docker Buildx
-        uses: docker/setup-buildx-action@v3
+      - name: Set up Python
+        uses: actions/setup-python@v6
+        with:
+          python-version: '3.11'
 
-      - name: Run SDK integration tests
+      - name: Install dev dependencies + run unit tests
         run: |
-          cd tests/integration
-          make test-sdk
+          cd sdk/python
+          make install-dev
+          make test
         timeout-minutes: 10
 
   build-wheels: