`<C-u>` doesn't move the cursor up

[IanEdington]

Describe the bug

<C-u> doesn't move the cursor down

Removing the vim.use<C-u> check from the when clause unblocked me, but I wanted to report this anyway since this probably isn't the desired solution.

To Reproduce

• remove other Keyboard Shortcuts for <C-u>
• open long document
• move cursor down document
• use <C-u>

Expected behavior should move the cursor up

Environment (please complete the following information):

• Extension (VsCodeVim) version: 1.23.1
• VSCode version: 1.69.0
• OS: MacOS 12.4

Additional context

default when = `editorTextFocus && vim.active && vim.use<C-u> && !inDebugRepl`

my when =      `editorTextFocus && vim.active && !inDebugRepl`