I don't understand why I can't do gradient fill on a square in manimgl-1.7.1 version

### Describe the error
I want to implement gradient filling inside the square in manimgl, but using set_color_by_gradient cannot achieve the effect I want.

### Code
```
from manimlib import*
sin=np.sin
cos=np.cos
My_color=[BLUE_E,WHITE]
class MainScene(Scene):
def construct(self) -> None:
tex=Tex(r"a^2+b^2=c^2",font_size=200).to_edge(UP)
sq=Square(fill_opacity=1)

tex.set_color_by_gradient(*My_color)
sq.set_color_by_gradient(*My_color)

self.add(tex,sq)
```
### Output

### Wish get help

### Environment
**OS System**: Window11
**manim version**: manimgl v1.7.2 But when I run the version number in the terminal, it shows 1.7.1
**python version**:python v3.12.8