Remove keyword 'final' from MinecraftHelp class.

[Ckblck]

The final keyword in the MinecraftHelp class is rendering impossible the extension of this class and the override of methods.

For instance, symbols of these methods cannot be modified as they have been hardcoded in a final class:

private @NonNull Component line(final int length) {
    return ComponentHelper.repeat(
                text("-", this.colors.primary, TextDecoration.STRIKETHROUGH),
                length
        );
}

private @NonNull Component branch() {
    return text("├─", this.colors.accent);
}

private @NonNull Component lastBranch() {
     return text("└─", this.colors.accent);
}

I did not submit a pull request as it may conflict with the current linting guidelines (if applicable).