8075560: Typo in Javadoc for java.util.Optional.equals()

Reviewed-by: alanb

jdk/src/java.base/share/classes/java/util/Optional.java

@@ -346,7 +346,7 @@ public final class Optional<T> {
      * </ul>
      *
      * @param obj an object to be tested for equality
-     * @return {code true} if the other object is "equal to" this object
+     * @return {@code true} if the other object is "equal to" this object
      * otherwise {@code false}
      */
     @Override

jdk/src/java.base/share/classes/java/util/OptionalDouble.java

@@ -244,7 +244,7 @@ public final class OptionalDouble {
      * </ul>
      *
      * @param obj an object to be tested for equality
-     * @return {code true} if the other object is "equal to" this object
+     * @return {@code true} if the other object is "equal to" this object
      * otherwise {@code false}
      */
     @Override

jdk/src/java.base/share/classes/java/util/OptionalInt.java

@@ -244,7 +244,7 @@ public final class OptionalInt {
      * </ul>
      *
      * @param obj an object to be tested for equality
-     * @return {code true} if the other object is "equal to" this object
+     * @return {@code true} if the other object is "equal to" this object
      * otherwise {@code false}
      */
     @Override

jdk/src/java.base/share/classes/java/util/OptionalLong.java

@@ -244,7 +244,7 @@ public final class OptionalLong {
      * </ul>
      *
      * @param obj an object to be tested for equality
-     * @return {code true} if the other object is "equal to" this object
+     * @return {@code true} if the other object is "equal to" this object
      * otherwise {@code false}
      */
     @Override