Answer array

const answers = [
  'Whatever.',
  'Sure.',
  'Whoa, chill out!',
  "Calm down, I know what I'm doing!",
];

export function hey(message) {
  const speech = message.trimEnd();
  if (speech == '') {
    return 'Fine. Be that way!';
  }

  const isQuestion = speech.endsWith('?') ? 1 : 0;
  const isShout =
    /[A-Z]{1}/.test(speech) && speech == speech.toUpperCase() ? 2 : 0;
  return answers[isQuestion + isShout];
}

In this approach you define an array that contains Bob’s answers, and each condition is given a score. The correct answer is selected from the array by using the score as the array index.

The String trimEnd method is applied to the input to eliminate any whitespace at the end of the input. If the string has no characters left, it returns the response for saying nothing.

The first half of the shout condition

/[A-Z]{1}/.test(speech)

is constructed from a regular expression pattern to ensure there is at least one uppercase letter character in the String. This is because the second half of the condition tests that the uppercased input is the same as the input. If the input were only "123" it would equal itself uppercased, but without letters it would not be a shout.

The uppercasing is done by using the String method toUpperCase.

The conditions of being a question and being a shout are assigned scores through the use of the ternary operator. For example, giving a question a score of 1 would use an index of 1 to get the element from the answers array, which is "Sure.".

Shortening

Note that when the body of an if statement is a short single line, both the test expression and the body could be put on the same line, like so

if (speech == '') return 'Fine. Be that way!';

It may not comply with some coding styles, but your team preferences may allow it.