Update quickstart.md

[jiabao422]

Please make sure these boxes are checked before submitting your PR, thank you!

• [ ] Make sure you follow VueCesium's contributing guide English | (中文).
• [ ] Make sure you are merging your commits to dev branch.
• [ ] Add some descriptions and refer to relative issues for your PR.

[zouyaoji]

hi @jiabao422，非常感谢您的 PR ，但是您没有使用 PR 标题规则 格式，请及时修改， 谢谢！

[jiabao422]

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