feat(materialcdn): bring materialcdn up.

[neoFelhz]

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What kind of change does this PR introduce? (check one with "x")

• Bug fix
• Feature
• Code style update (formatting, local variables)
• Refactoring (no functional changes, no api changes)
• Build related changes
• CI related changes
• Other... Please describe:

Does this PR introduce a breaking change? (check one with "x")

• Yes
• No

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Description

Add support for using Private CDN to boost the theme

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Verification steps

Please clone the code in this branch, and then run a test.
You can use the https://materialcdn.nfz.moe/material-theme/hexo as the base to test. I made this Public CDN for hexo-theme-material.

I have already test it, and it really works!