Fix issues noticed in Ubuntu setup

- Use pip build in dev setup, remove defaults channel
- Fix backend coverage issue

Author: PardhavMaradani

devtools/conda-envs/dev_env.yaml

@@ -1,15 +1,15 @@
 name: mdadash-dev
 channels:
   - conda-forge
+  - nodefaults
 dependencies:
   # Base depends
   - python
   - pip
+  - pip:
+    - build
 
   # Development
   - nodejs
   - twine
   - ruff
-
-  # Build
-  - build

devtools/conda-envs/test_env.yaml

@@ -1,6 +1,7 @@
 name: mdadash-test
 channels:
   - conda-forge
+  - nodefaults
 dependencies:
   # Base depends
   - python

docs/requirements.yaml

@@ -1,6 +1,7 @@
 name: mdadash-docs
 channels:
   - conda-forge
+  - nodefaults
 
 dependencies:
   # Base depends

mdadash/backend/kernel/manager.py

@@ -86,6 +86,20 @@ async def start(self) -> None:
 
     async def stop(self) -> None:
         """Stop the async kernel"""
+        # This seems to be the only reliable way to get coverage results
+        # back from the kernel started with AsyncKernerlManager on Ubuntu.
+        # This should not impact existing app functionality.
+        coverage_flush = """
+        try:
+            import coverage
+            cov = coverage.Coverage.current()
+            if cov:
+                cov.stop()
+                cov.save()
+        except ImportError:
+            pass
+        """
+        self.kc.execute(coverage_flush)
         self._is_running = False
         # wait for listen task to completely exit
         await self.listen_task