Format a class body that holds nothing but semicolons

[abashev]

Brings over google/google-java-format#1104, a fix from google-java-format 1.23.

The bug

class A { ; } failed with error: expected token: ';'; generated } instead. javac drops a stray semicolon from the member list, so the body looked empty and the formatter wrote {} without ever emitting the ; that was still in the input. A semicolon between real members was already handled; only a body with no member at all lost it. The same happened to interface B { ; }, record R(int a) { ; }, @interface H { ; } and new Object() { ; }.

From upstream, with the author kept

• Handle classes with no members and semi-colons google/google-java-format#1104 by Liam Miller-Cushon, commit authored by them. An empty body whose next token is ; writes those semicolons one per line at the member indent before the closing brace, as the member list does. The upstream golden SemicolonInClass comes with it, with the expected output in this project's style.

Added here

• The golden ojf-semicolon-only-body: an interface, an enum, a record, an annotation type and an anonymous class with only semicolons in the body, two semicolons in a row, a comment after the opening brace, and a semicolon in front of a real member, which took the existing path all along.

Checked

• Both goldens fail on main and pass with the change; the output is stable on a second run.
• ./gradlew :open-java-format:test on JDK 21: 1505 tests, all green.
• The 15,747 files of the JDK 21 sources format exactly as before.