Use 'name' in DAP start_thread function
The DAP start_thread helper function has a 'name' parameter that is
unused.  Apparently I forgot to hook it up to the thread constructor.
This patch fixes the oversight.
diff --git a/gdb/python/lib/gdb/dap/startup.py b/gdb/python/lib/gdb/dap/startup.py
index 15d1fb9..eba0721 100644
--- a/gdb/python/lib/gdb/dap/startup.py
+++ b/gdb/python/lib/gdb/dap/startup.py
@@ -35,7 +35,7 @@
     """Start a new thread, invoking TARGET with *ARGS there.
     This is a helper function that ensures that any GDB signals are
     correctly blocked."""
-    result = gdb.Thread(target=target, args=args, daemon=True)
+    result = gdb.Thread(name=name, target=target, args=args, daemon=True)
     result.start()