Is your feature request related to a problem? Please describe.
When using VSCode VIM, being able to use VIM bindings in more than just the text editor could improve peoples workflow substantially. When hitting command/control + p to open the file palette, only being able to browse the files up and down with arrow keys is something that could be greatly improved.
Describe the solution you'd like
This could easily be solved by allowing the user to browse this file list when hitting ctrl + k with ctrl + j for going up and down in the file list. This is a very common command for browsing file list and options in many other programs and applications that apply the VIM bindings any some way.
Additional context
When mentioning file list this is the component I'm talking about.

as a workaround you could set command/ctrl + j to the workbench.action.quickOpenSelectNext and command/ctrl + k to the workbench.action.quickOpenSelectPrevious when you're inside QuickOpen (thats the official vscode name for what you're calling file list 
You can get to that screen with cmd-shift-p then type keyboard shortcuts
Most helpful comment
as a workaround you could set command/ctrl + j to the
workbench.action.quickOpenSelectNextand command/ctrl + k to theworkbench.action.quickOpenSelectPreviouswhen you're insideQuickOpen(thats the official vscode name for what you're calling file listYou can get to that screen with cmd-shift-p then type keyboard shortcuts