ilm: Handle DeleteAllVersions action differently for DEL markers (#19481)

i.e., this rule element doesn't apply to DEL markers.

This is a breaking change to how ExpiredObejctDeleteAllVersions
functions today. This is necessary to avoid the following highly probable
footgun scenario in the future.

Scenario:
The user uses tags-based filtering to select an object's time to live(TTL). 
The application sometimes deletes objects, too, making its latest
version a DEL marker. The previous implementation skipped tag-based filters
if the newest version was DEL marker, voiding the tag-based TTL. The user is
surprised to find objects that have expired sooner than expected.

* Add DelMarkerExpiration action

This ILM action removes all versions of an object if its
the latest version is a DEL marker.

```xml
<DelMarkerObjectExpiration>
    <Days> 10 </Days>
</DelMarkerObjectExpiration>
```

1. Applies only to objects whose,
  • The latest version is a DEL marker.
  • satisfies the number of days criteria
2. Deletes all versions of this object
3. Associated rule can't have tag-based filtering

Includes,
- New bucket event type for deletion due to DelMarkerExpiration

cmd/erasure-object.go

@@ -1886,12 +1886,13 @@ func (er erasureObjects) DeleteObject(ctx context.Context, bucket, object string
 			// based on the latest objectInfo and see if the object still
 			// qualifies for deletion.
 			if gerr == nil {
-				evt := evalActionFromLifecycle(ctx, *lc, rcfg, replcfg, goi)
 				var isErr bool
+				evt := evalActionFromLifecycle(ctx, *lc, rcfg, replcfg, goi)
 				switch evt.Action {
-				case lifecycle.NoneAction:
-					isErr = true
-				case lifecycle.TransitionAction, lifecycle.TransitionVersionAction:
+				case lifecycle.DeleteAllVersionsAction, lifecycle.DelMarkerDeleteAllVersionsAction:
+					// opts.DeletePrefix is used only in the above lifecycle Expiration actions.
+				default:
+					// object has been modified since lifecycle action was previously evaluated
 					isErr = true
 				}
 				if isErr {