function convertJSFBTLeafToRuntimeInputText(leaf /*: $ReadOnly<TableJSFBTTreeLeaf> */) /* : PatternString */ {
  return replaceClearTokensWithTokenAliases(leaf.text, leaf.tokenAliases);
}
Helper method to convert jsfbt tree leaf to runtime input leaf by:
 1. Stripping away keys (e.g desc and tokenAliases) that are unneccessary
   for runtime and only keep the `text` key.
 2. Replacing clear token names in the text with mangled tokens.