Setting frame width and frame heigh is only taking frame_width into account.

Nobody has claimed this yet.

When running this script:
```py
from manim import *
config["pixel_width"] = 100
config["pixel_height"] = 100
config["frame_width"] = 1
config["frame_height"] = 4
class Example(Scene):
def construct(self):
ar = Arrow(ORIGIN,2*UP)
self.add(ar)
```
My expectation would be: a 100x100 pixel image, where one can see the whole arrow (as it is in the field of view.)

Instead, I got this:


A 100x100 pixel image, however not the whole arrow is visible.

This means, there is a problem with setting frame_height.

Run the provided Python script and compare the resulting 100x100 image with the expected view of the complete arrow. Trace where frame_width and frame_height are applied, then verify that changing frame_height affects the field of view and that the whole arrow is visible.

Written by the indexing model from the issue text.