Fix Viewer Crashing on Load of Wrong OSCAL Doc Type

[zclarkEDC]

Fix for #240

Should work for Catalogs, SSPs, and Components.

[kylelaker]

Should we move ErrorBoundary into it's own file and export it so that we can have other error boundaries all over?

[kylelaker]

That would probably also mean that ErrorBoundary should accept an errorFormatter prop or something like that so that you can override how an error is displayed at a specific part of the application:

snippets of changed functions:

function defaultFormatter(error) {
  return (
    <Alert severity="error">
      Yikes! Something went wrong loading the OSCAL data. Sorry, we&apos;ll look
      into it. ({error.message})
    </Alert>
  );
);

export class ErrorBoundary extends React.Component {
  constructor(props) {
    super(props)
    this.errorFormatter = props.errorFormatter ?? defaultFormatter;
    this.state = { error: undefined };
  }

  render() {
    if (this.state.error !== undefined) {
      return this.errorFormatter(this.state.error);
    }
    return this.props.children;
  }
}

Idk if the errorFormatter should go on this or this.state. I also don't know if I like that name.