Add ItemStack context to `getCoolDownTicks` in shield item class

[IMB11]

Would be useful for enchantments that affect cooldown ticks.

[IMB11]

Example:

@Override
    public int getCoolDownTicks(@Nullable ItemStack itemStack) {

        if (itemStack != null) {
            ... = itemStack.getEnchantments().getLevel(...);

            return super.getCoolDownTicks() * ...;
        }

        return super.getCoolDownTicks();
    }
    ```

[CringeStar]

Yeah, looks good! So I just need to change this line to public int getCoolDownTicks(@Nullable ItemStack itemStack) {?

[CringeStar]

Done in 1.21.3 and 1.21.4 versions, not sure how far we'll backport.

[github-actions[bot]]

Marked stale due to inactivity.

[StellarWind22]

Okay, so this has been added in newer versions & will be back-ported eventually, I've been working on getting 2.0 more stable before attempting a backport.