Write isPalindrome function

[kartamyshev]

const testCases = [
  {
    actual: isPalindrome('race car'),
    expected: true
  },
  {
    actual: isPalindrome(`Madam I'm Adam`),
    expected: true
  },
  {
    actual: isPalindrome('Madam'),
    expected: true
  },
  {
    actual: isPalindrome('Apapa'),
    expected: true
  },
  {
    actual: isPalindrome('this is mine enims i sih t'),
    expected: true
  },
  {
    actual: isPalindrome('This is a random string'),
    expected: false
  },
  {
    actual: isPalindrome('Graph'),
    expected: false
  },
  {
    actual: isPalindrome('Black Sabbath'),
    expected: false
  },
];