Symfony version(s) affected: 4.2.7

Description
When I updated to 4.2.7, I can't access to my routes if I add a '/', it gives me a Notice: Undefined offset: 1.
I cleared the cache using : bin/console cache:clear, doesn't work
then I deleted the folder var/cache : doesn't work

How to reproduce
If I access to "/api/collaborators" it works but accessing to "/api/collaborators/" gives the error

Additional context