readline: fix the REPL on editor mode crashing during tab completion

[cola119]

Fixes#43528. This PR fixes the REPL on editor mode crashing during tab completion.

The root cause of this issue is that commonPrefix could receive an empty array of completions because of #41632.

On editor mode, the completions are converted into the common prefix string in REPLServer.prototype.completeOnEditorModeL1603 (I'm not sure why this wrapper is needed). And then [kTabCompleter]() is called as a callback with the completion as its argument.

node/lib/repl.js

Lines 1596 to 1607 in 6f924ac

	REPLServer.prototype.completeOnEditorMode=(callback)=>(err,results)=>{
	if(err)returncallback(err);
	const{0: completions,1: completeOn=''}=results;
	letresult=ArrayPrototypeFilter(completions,Boolean);
	if(completeOn&&result.length!==0){
	result=[commonPrefix(result)];
	}
	callback(null,[result,completeOn]);
	};

For example, the completions for a are ['async', 'await', 'Array', ...] (note that #41632 made REPL case-incentive) and their common prefix string is '' (the return value of commonPrefix(['async', 'await', 'Array', ...])).
This means the completions is [''] when [kTabCompleter]() is called, and commonPrefix([]) will be called at L670.

node/lib/internal/readline/interface.js

Lines 662 to 672 in 6f924ac

	[kTabCompleter](lastKeypressWasTab,{0: completions,1: completeOn}){
	// Result and the text that was completed.
	if(!completions||completions.length===0){
	return;
	}
	// If there is a common prefix to all matches, then apply that portion.
	constprefix=commonPrefix(
	ArrayPrototypeFilter(completions,(e)=>e!=='')
	);

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/44917/

[nodejs-github-bot]

Landed in 593de05