Include bypass to allow merge-mantine-theme.ts to accept more than 10 shades.

[TheHarrisButler]

I am trying to use the 11th shade as a primary shade. But mergeTheme has explicit bounds checks on shade. Can you add a way to bypass this check?

const theme = useTheme({
     ...
    primaryShade: { light: 10, dark: 7 },  // game over error:  Invalid theme.primaryShade, it accepts only 0-9 integers or an object { light: 0-9, dark: 0-9 }
    ...
})

function isValidPrimaryShade(shade: number) {
  if (shade < 0 || shade > 9) {
    return false;
  }

  return parseInt(shade.toString(), 10) === shade;
}