lib.ec.Local._run(): Interpret env as mod_env

An env argument environment passed to Local._run() entirely replaces
the environment. Make it modify the enviroment instead.

Signed-off-by: Jan Lindemann <jan@janware.com>

src/python/jw/pkg/lib/ec/Local.py

@@ -75,6 +75,11 @@ class Local(Base):
             # -- non-interactive mode
             stdin = asyncio.subprocess.DEVNULL if cmd_input is None else asyncio.subprocess.PIPE
 
+            if env:
+                new_env = os.environ.copy()
+                new_env.update(env)
+                env = new_env
+
             proc = await asyncio.create_subprocess_exec(
                 *cmd,
                 stdin=stdin,