REPL: Limit method lookup when completing kwargs (#56963)

(cherry picked from commit 10e20f1)

Author: IanButterworth

stdlib/REPL/src/REPLCompletions.jl

@@ -949,7 +949,7 @@ function complete_keyword_argument(partial, last_idx, context_module)
     kwargs_flag == 2 && return fail # one of the previous kwargs is invalid
 
     methods = Completion[]
-    complete_methods!(methods, funct, Any[Vararg{Any}], kwargs_ex, -1, kwargs_flag == 1)
+    complete_methods!(methods, funct, Any[Vararg{Any}], kwargs_ex, shift ? -1 : MAX_METHOD_COMPLETIONS, kwargs_flag == 1)
     # TODO: use args_ex instead of Any[Vararg{Any}] and only provide kwarg completion for
     # method calls compatible with the current arguments.