message: fix(update-server): Fix hash in SSH key upload response message
  The `f` was forgotten from an f-string, causing the "Added key {hashval}" response to an SSH key upload to include the literal string "{hashval}".
diff: @@ -148,7 +148,7 @@ async def add(request: web.Request) -> web.Response:
  ak.write(f'{pubkey}\n')
  return web.json_response(
  - data={'message': 'Added key {hashval}',
  + data={'message': f'Added key {hashval}',
  'key_md5': hashval},
  status=201)
  