remote/client: use non-deprecated iscoroutinefunction from inspect module

asyncio.iscoroutinefunction() is deprecated [1] since Python 3.14 [2].
Use inspect.iscoroutinefunction() instead.

[1] https://docs.python.org/3/deprecations/index.html#pending-removal-in-python-3-16
[2] python/cpython@bc9d92c

Signed-off-by: Bastian Krause <bst@pengutronix.de>

Author: Bastian-Krause

labgrid/remote/client.py

@@ -1759,6 +1759,8 @@ def __str__(self):
 
 
 def main():
+    import inspect
+
     basicConfig(
         level=logging.WARNING,
         stream=sys.stderr,
@@ -2214,7 +2216,7 @@ def main():
             logging.debug("Started session")
 
             try:
-                if asyncio.iscoroutinefunction(args.func):
+                if inspect.iscoroutinefunction(args.func):
                     if getattr(args.func, "needs_target", False):
                         place = session.get_acquired_place()
                         target = session._get_target(place)