fix(coordinode): use sources mapping to include package files in wheel

packages = ["coordinode"] looks for coordinode/coordinode/ subdir which
does not exist — pyproject.toml is inside the package directory itself.
sources = {"." = "coordinode"} maps the current dir as the coordinode
package, producing a wheel with actual Python files.

The 0.4.1 wheel contained 0 Python files, making the package unimportable.

Author: polaz

coordinode/pyproject.toml

@@ -51,7 +51,7 @@ raw-options = {root = ".."}
 version-file = "_version.py"
 
 [tool.hatch.build.targets.wheel]
-packages = ["coordinode"]
+sources = {"." = "coordinode"}
 
 [tool.pytest.ini_options]
 asyncio_mode = "auto"