Invalid `isBoundToPoint` function implementation

[stockiNail]

The implementation of isBoundToPoint is wrong.

If I set xValue: 0 and yValue: 0, it returns false and that's not correct because I want to have the annotation with center point at value 0, 0.

chartjs-plugin-annotation/src/helpers/helpers.options.js

Lines 54 to 56 in b274a21

	export function isBoundToPoint(options) {
	return options && (options.xValue || options.yValue);
	}