fix:url not match correctly when the url include brackets

[RolandMa1986]

We are using dom-to-image-more in an electron app. So all the resources are loaded from the local file system. We found that the 'URL_REGEX' not handle the url correctly when the url include brackets.
such as:

@font-face { font-family: codicon; font-display: block; src: url("file:///C:/Program%20Files%20(x86)/<app>/resources/app/lib/frontend/front.ttf") format("truetype"); }

The solution is that matching the quote in the first place after left bracket and should be matched before right bracket.

[RolandMa1986]

hi @IDisposable,
Can you help review the PR?