Add test for successful connection registration numerics (#233)

And Python version bump so I can use the walrus.

.github/workflows/lint.yml

@@ -13,10 +13,10 @@ jobs:
 
     - uses: actions/checkout@v2
 
-    - name: Set up Python 3.7
+    - name: Set up Python 3.11
       uses: actions/setup-python@v2
       with:
-        python-version: 3.7
+        python-version: 3.11
 
     - name: Cache dependencies
       uses: actions/cache@v2