[Client JS] ajaxErrors doesn't support fetch

[aoxls]

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• Question or discussion
• Bug
• Requirement
• Feature or performance improvement

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Requirement or improvement

Hi ~ I found that ajaxErrors doesn't contains the errors of fetch, should it be supported ?
By the way, would you please conside to add a params in registermethod, to customize ajaxError, just like some business exception?

[Fine0830]

PromiseErrors is able to catch fetch errors

[aoxls]

PromiseErrors is able to catch fetch errors

PromiseErrors just catches the unhandled rejections, it won't work if I catched in my code, maybe it's better to create an interceptor?

[Fine0830]

Let's fix this.