Creating IndexOptions using expireAfter method sets wrong options

[mozzer39]

Hi!
I have noticed a bug in IndexOptions class. Using expireAfter(Duration duration) method should set expire field with given expiration time, but duration parameter is not used and unique option is set instead.

spring-data-mongodb/spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/index/IndexOptions.java

Lines 86 to 91 in f910839

	public static IndexOptions expireAfter(Duration duration) {
	IndexOptions options = new IndexOptions();
	options.unique = Unique.YES;
	return options;
	}

[christophstrobl]

Now that is something. Thank you @mozzer39 for reporting the issue. We'll get that fixed!