let valueStr;
    if (typeof value === 'string' || typeof value === 'boolean') {
      valueStr = value.toString();
    }
Validates the type of fbt construct inside <fbt>.
Currently detected:
  <fbt:param>, <FbtParam>
  <fbt:enum>,  <FbtEnum>
  <fbt:name>,  <FbtName>
  etc...
@param node The node that may be a JSX fbt construct
@return Returns the name of a corresponding handler (fbt construct).
If a child is not valid, it is flagged as an Implicit Parameter (`implicitParamMarker`)