string block collaps on empty line

[Pankraz76]

when removing // tmp fix comment the block collapses like seen below:

            {
                {
                    """
                    import java.util.List;
                    import java.lang.Deprecated;

                    @Deprecated
                    class Test {}
                    """
                },
                // fixme:
                //  this is a bug in formatter
                //  when line is not blank but having white spaced block remains stable
                {
                    """
                    // tmp fix 
                    @Deprecated
                    class Test {}
                    """
                },
                {"""

                @Deprecated
                class Test {}
                """}
            },

• https://github.com/palantir/palantir-java-format/pull/1337/files#r2182497166