Remove fork from settingsContext.ts

[thevaizman]

Currently, we save the user settings in the browser's localStorage.
These settings include:

export enum Setting {
  EditorCodeType = 'editor::codetype',
  VmChain = 'vm::chain',
  VmFork = 'vm::fork',
}

We should consider removing VmFork from here since this is somewhat a weird behavior. I'd imagine users would rather be on the latest fork by default instead of staying "stuck" on the last fork they manually chose.