Fix FileTree component height

What does this MR do and why?

This MR fixes:

1. File tree jumps around when collapsing/expandin... (#395795 - closed)
2. Code review bar hides last file in file browser (#399622 - closed)
3. MR Diff > Gap between the files browser and the... (#392968 - closed)
4. Merge request diff view makes file tree and fil... (#396373 - closed)

Most of these are a regression from Use virtual scroller for diffs file tree (!111518 - merged).

It does so by doing the following:

1. Switches from ResizeObserver to window resize events
2. Inherits the height from parent element by limiting scroll target element overflow with overflow: hidden
3. Respects ReviewBar component height
4. Uses row height to calculate scroll height on narrow screens

Important: this MR does not introduce new tests, we should handle that in another MR: Add test coverage for diffs FileTree component (#408383 - closed).

Screenshots or screen recordings

Before	After

How to set up and validate locally

Review bar compatibility

1. Open a merge request with many files changed
2. Start a review by writing a comment on one of the lines
3. The Review bar should not cover the last file in the file tree

Narrow screen

1. Open a merge request with 1-5 files changed
2. Set your viewport width to less than 990 pixels.
3. File tree height should not exceed the amount of files in the list