Parallel Gateway continues if multiple tokens are received on the same path

**Describe the bug**
I have a process with a parallel gateway that waits on two branches, one of which has a loop which checks every hour whether a variable is true.
I would expect that the gateway waits for both branches to complete before proceeding, but it actually proceeds if the same branch completes twice.

This can happen because a Message Catch Event can spawn a new token, which gets sent down the same branch again.

**Expected behavior**
I would expect the parallel gateway to wait for a token from each branch to arrive, rather than just waiting for 2 tokens to arrive from the same branch.

Comienza reproduciendo el proceso descrito: un parallel gateway con dos ramas, incluido un bucle y un Message Catch Event que puede enviar varios tokens por una rama. Rastrea cómo el gateway cuenta los tokens entrantes y distingue las ramas. Se considera terminado cuando el gateway solo continúa después de recibir un token de cada rama, incluso cuando una rama recibe varios tokens.

Escrito por el modelo de indexación a partir del texto del issue.