fix(mandala): remove rotation and color animation

[caugner]

Summary

Fixes #9347.

Problem

The Mandala animations have two problems:

1. The rotation causes a significant CPU and GPU usage (see issue above).
2. The color animation on the MDN Plus page distracts from the content.

Solution

Remove the rotation and the color animation.

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Screenshots

Before

Screen.Recording.2023-10-31.at.15.57.16.mov

Screen.Recording.2023-10-31.at.15.57.25.mov

After

Screen.Recording.2023-10-31.at.15.56.59.mov

Screen.Recording.2023-10-31.at.15.57.38.mov

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How did you test this change?

Ran yarn && yarn dev and opened http://localhost:3000/en-US/ and http://localhost:3000/en-US/plus locally.

[AnujaRajput727]

The changes in the screenshot look OK!