Fix an @link now that @autoservice and its annotations are not in the…

… same maven module

RELNOTES=n/a

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=239811641

service/annotations/src/main/java/com/google/auto/service/AutoService.java

@@ -23,12 +23,11 @@
 import java.lang.annotation.Target;
 
 /**
- * An annotation for service providers as described in {@link java.util.ServiceLoader}. The {@link
- * com.google.auto.service.processor.AutoServiceProcessor} generates the configuration files which
- * allows service providers to be loaded with {@link java.util.ServiceLoader#load(Class)}.
+ * An annotation for service providers as described in {@link java.util.ServiceLoader}. The
+ * annotation processor generates the configuration files that allow the annotated class to be
+ * loaded with {@link java.util.ServiceLoader#load(Class)}.
  *
- * <p>Service providers assert that they conform to the service provider specification.
- * Specifically, they must:
+ * <p>The annotated class must conform to the service provider specification. Specifically, it must:
  *
  * <ul>
  *   <li>be a non-inner, non-anonymous, concrete class