message: doc select multi support
diff: @@ -2,8 +2,6 @@ import React, { useState, useEffect } from "react";
  import SearchIcon from "@material-ui/icons/Search";
  import IconButton from "@material-ui/core/IconButton";
  import { createStyles, makeStyles, Theme } from "@material-ui/core/styles";
  -import { TextField } from "@material-ui/core";
  -import Typography from "@material-ui/core/Typography";
  import Chip from "@material-ui/core/Chip";
  const useStyles = makeStyles((theme: Theme) =>
  @@ -57,25 +55,33 @@ const DocSelect = (props: Props) => {
  ...oldValues,
  collection: collectionPath,
  config: config,
  - onSubmit: (value: any) => {
  - onSubmit([value]);
  + onSubmit: (newItem: any) => {
  + if (value) onSubmit([...value, newItem]);
  + else onSubmit([newItem]);
  },
  }));
  };
  + const handleDelete = (index: number) => {
  + let newValue = [...value];
  + newValue.splice(index, 1);
  + onSubmit(newValue);
  + };
  return (
  <div className={classes.root}>
  <IconButton onClick={handleClick}>
  <SearchIcon />
  </IconButton>
  {value &&
  - value.map((doc: any) => (
  + value.map((doc: any, index: number) => (
  <Chip
  label={config.primaryKeys.map(
  (key: any) => `${doc.snapshot[key]} `
  )}
  //onClick={handleClick}
  - //onDelete={handleDelete}
  + onDelete={() => {
  + handleDelete(index);
  + }}
  className={classes.chip}
  />
  ))}
  