Update exception variable names

Consistently use `ex` for caught exception and `cause` for Exception
constructor arguments.

Issue gh-8945

acl/src/test/java/org/springframework/security/acls/domain/AclImplTests.java

@@ -628,8 +628,8 @@ public class AclImplTests {
 							((AuditableAccessControlEntry) ac).isAuditFailure()));
 				}
 			}
-			catch (IllegalAccessException e) {
-				e.printStackTrace();
+			catch (IllegalAccessException ex) {
+				ex.printStackTrace();
 			}
 
 			return acl;

acl/src/test/java/org/springframework/security/acls/jdbc/JdbcMutableAclServiceTests.java

@@ -121,9 +121,9 @@ public class JdbcMutableAclServiceTests extends AbstractTransactionalJUnit4Sprin
 			// new DatabaseSeeder(dataSource, new
 			// ClassPathResource("createAclSchemaPostgres.sql"));
 		}
-		catch (Exception e) {
-			e.printStackTrace();
-			throw e;
+		catch (Exception ex) {
+			ex.printStackTrace();
+			throw ex;
 		}
 	}