isEqualWith has wrong return type for customizer

[felixfbecker]

From the docs:

If customizer returns undefined, comparisons are handled by the method instead.

interface IsEqualCustomizer {
  (value: any, other: any, indexOrKey?: number | string): boolean;
}

should be

interface IsEqualCustomizer {
  (value: any, other: any, indexOrKey?: number | string): boolean | void;
}