fix: 调整Logo长宽比，防止显示被拉伸

[Anyexyz]

What this PR does / why we need it?

调整Logo长宽比，防止显示被拉伸

Summary of your change

将 favicon.png 文件统一长宽为500px，放大填充原图标。

Please indicate you've done the following:

• Made sure tests are passing and test coverage is added if needed.
• Made sure commit message follow the rule of Conventional Commits specification.
• Considered the docs impact and opened a new docs issue or PR with docs changes if needed.

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[wanghe-fit2cloud]

感谢支持，针对调整后的图片，建议进一步压缩以减少文件大小。

[Anyexyz]

感谢支持，针对调整后的图片，建议进一步压缩以减少文件大小。

已压缩