[NETBEANS-8278] Fixing yield handling in introduce method fix.

[lahodaj]

Consider code like:

package javaapplication1;

public class JavaApplication1 {

    public static void main(String[] args) {
        String str = switch (args.length) {
            case 0 -> {
                System.err.println("3");
                yield "";
            }
            default -> "";
        };
    }
    
}

Select these lines:

                System.err.println("3");
                yield "";

In the Alt-Enter popup, choose Introduce Method.... This leads to:

    public static void main(String[] args) {
        String s = "GTK-test";
        String str = switch (args.length) {
            case 0 -> {
                method();
            }
            default -> "";
        };
    }

    private static void method() {
        System.err.println("3");
        yield "";
    }

which is obviously wrong - it should be something like:

    public static void main(String[] args) {
        String s = "GTK-test";
        String str = switch (args.length) {
            case 0 -> {
                yield method();
            }
            default -> "";
        };
    }

    private static String method() {
        System.err.println("3");
        return "";
    }

This patch attempts to change the introduce hint to do the correct transformation.

closes #8278

---

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[mbien]

would be good to rebase this one. Might be something for early NB 29? (freeze for NB28 is about a week away)

[mbien]

testPatternSwitch1: org.netbeans.api.java.source.gen.SwitchTest might have found something