Handle JUnit4 ExpectedException Rule as part of JUnit4 -> 5 recipe

[sambsnyd]

org.junit.rules.ExpectedException appears in a few places in Design Partner 1's code base.

Per its documentation, ExpectedException is used like this:

                package org.openrewrite.java.testing.junit5;

                import org.junit.Rule;
                import org.junit.Test;
                import org.junit.rules.ExpectedException;
                
                public class SimpleExpectedExceptionTest {
                    @Rule
                    public ExpectedException thrown = ExpectedException.none();
                
                    @Test
                    public void throwsNothing() {
                        // no exception expected, none thrown: passes.
                    }
                
                    @Test
                    public void throwsExceptionWithSpecificType() {
                        thrown.expect(NullPointerException.class);
                        throw new NullPointerException();
                    }
                }

One way of translating this to JUnit 5 is:

                package org.openrewrite.java.testing.junit5;
                
                import org.junit.jupiter.api.Test;
                
                import static org.junit.jupiter.api.Assertions.assertThrows;
                
                public class SimpleExpectedExceptionTest {
                    @Test
                    public void throwsNothing() {
                        // no exception expected, none thrown: passes.
                    }
                
                    @Test
                    public void throwsExceptionWithSpecificType() {
                        assertThrows(NullPointerException.class, () -> {
                            throw new NullPointerException();
                        });
                    }
                }