comment: use exec configuration for the lock target

Author: aignas

python/uv/private/lock.bzl

@@ -274,6 +274,7 @@ _lock_run = rule(
         "lock": attr.label(
             doc = "The lock target that is doing locking in a build action.",
             providers = [_RunLockInfo],
+            cfg = "exec",
         ),
         "output": attr.string(
             doc = """\