String wrapping is not idempotent

This happened with the all deps jar from github, for both versions `1.15.0` and `1.16.0`.

```
$ java --version
openjdk 17.0.6 2023-01-17
OpenJDK Runtime Environment (build 17.0.6+10)
OpenJDK 64-Bit Server VM (build 17.0.6+10, mixed mode)
```

Example code is

```java
package com.example;

public class TestFormat {

public void main() {
var value = 1;
var responseMessage =
switch (value) {
case 1 -> "This is a long string;This is a long string;This is a long string;This is a long string;This is a long string;This is a long string;This is a long string;";
case 2 -> "some short string";
case 3 -> "some medium string some medium string some medium string some medium string";
};
}
}
```

Now these strings in the switch statement will be different formatted depending on how often I call google java format.
Weirdly enough, the cosium maven plugin (gjf `v1.15.0`) does not change the strings in this example at all. This would be preferable for me, but mostly I want a consistent format.

```
## executing preview only
$ java -jar /home/dev/dev/libs/google-java-format-1.15.0-all-deps.jar Testformat.java
package com.example;

public class TestFormat {

public void main() {
var value = 1;
var responseMessage =
switch (value) {
case 1 -> "This is a long string;This is a long string;This is a long string;This is a"
+ " long string;This is a long string;This is a long string;This is a long"
+ " string;";
case 2 -> "some short string";
case 3 -> "some medium string some medium string some medium string some medium string";
};
}
}

## applying changes
$ java -jar /home/dev/dev/libs/google-java-format-1.15.0-all-deps.jar -r Testformat.java

## executing preview only
$ java -jar /home/dev/dev/libs/google-java-format-1.15.0-all-deps.jar Testformat.java
package com.example;

public class TestFormat {

public void main() {
var value = 1;
var responseMessage =
switch (value) {
case 1 -> "This is a long string;This is a long string;This is a long string;This is a"
+ " long string;This is a long string;This is a long string;This is a long"
+ " string;";
case 2 -> "some short string";
case 3 -> "some medium string some medium string some medium string some medium string";
};
}
}
```

The expectation would be that once I format a file every future format call would not change anything anymore as long as nothing was changed on the file.