Spring HATEOAS heap exhaustion through unbounded internal caching

Spring HATEOAS maintains an unbounded static cache of StringLinkRelation instances keyed on attacker-supplied strings. Affected versions: Spring HATEOAS 1.5.0 through 1.5.6; 2.3.0 through 2.3.4; 2.4.0 through 2.4.1; 2.5.0 through 2.5.2; 3.0.0 through 3.0.3.