REPL: Handle message from complete_methods! when max methods is hit (#57138)

(cherry picked from commit 88c71dd)

Author: IanButterworth

stdlib/REPL/src/REPLCompletions.jl

@@ -1037,6 +1037,9 @@ function complete_keyword_argument(partial, last_idx, context_module)
     last_word = partial[wordrange] # the word to complete
     kwargs = Set{String}()
     for m in methods
+        # if MAX_METHOD_COMPLETIONS is hit a single TextCompletion is return by complete_methods! with an explanation
+        # which can be ignored here
+        m isa TextCompletion && continue
         m::MethodCompletion
         possible_kwargs = Base.kwarg_decl(m.method)
         current_kwarg_candidates = String[]