Remove the pure attribute from @Contract

Closes spring-projectsgh-33820

spring-core/src/main/java/org/springframework/lang/Contract.java

@@ -42,12 +42,12 @@
  *
  * The constraints denote the following:<br/>
  * <ul>
- * <li> _ - any value</li>
- * <li> null - null value</li>
- * <li> !null - a value statically proved to be not-null</li>
- * <li> true - true boolean value</li>
- * <li> false - false boolean value</li>
- * <li> fail - the method throws an exception, if the arguments satisfy argument
+ * <li> <code>_</code> - any value</li>
+ * <li> <code>null</code> - null value</li>
+ * <li> <code>!null</code> - a value statically proved to be not-null</li>
+ * <li> <code>true</code> - true boolean value</li>
+ * <li> <code>false</code> - false boolean value</li>
+ * <li> <code>fail</code> - the method throws an exception, if the arguments satisfy argument
  * constraints</li>
  * </ul>
  * <p>Examples:
@@ -60,7 +60,8 @@
  *
  * @author Sebastien Deleuze
  * @since 6.2
- * @see <a href="https://github.com/uber/NullAway/wiki/Configuration#custom-contract-annotations">NullAway custom contract annotations</a>
+ * @see <a href="https://github.com/uber/NullAway/wiki/Configuration#custom-contract-annotations">
+ * NullAway custom contract annotations</a>
  */
 @Documented
 @Retention(RetentionPolicy.CLASS)
@@ -71,10 +72,4 @@
 	 * Contains the contract clauses describing causal relations between call arguments and the returned value.
 	 */
 	String value() default "";
-
-	/**
-	 * Specifies if this method is pure, i.e. has no visible side effects. This may be used for more precise data flow analysis, and
-	 * to check that the method's return value is actually used in the call place.
-	 */
-	boolean pure() default false;
 }