Fix incorrect url when deploy.

[richex-cn]

I got incorrect url when I using hexo d. They inserted this format of URL in my LeanCloud Counter Class:

And leancloud.memo:

But the request URL like it, where QueryString has only one slash {"url":"/530.html"} cause not working:

https://example.com/1.1/classes/Counter?where=%7B%22url%22%3A%22%2F530.html%22%7D

I fixed this problem, if this change has no side effects, merge it.

[CLAassistant]

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