Fix bad syntax in doc comment

The doc comments for several methods (requestDragging(),
requestDelegating(), performClick(), performLongClickAndStartDrag()) had
spurious {@link code (which I think was a copy/paste error), resulting
in garbled reference doc.

No change to code, docs-only fix.

Fixed docs are staged to:

http://go/dac-stage/reference/android/accessibilityservice/TouchInteractionController
http://go/dac-stage/reference/kotlin/android/accessibilityservice/TouchInteractionController

Flag: DOCS_ONLY
Test: [ABTD docs build]
Fixes: 418690558
Change-Id: I317f3d76729243473d2064ac68b31702066c0030