[Notify failure] Automatically count down retries

[Noordsestern]

A task worker must count down the number of retries itself (which is weird).

Automatically count down retries in case a process instance has one, so the automationeer does not need to:

*** Test Case ***
Demo retry count down
    ${retries}    Set Variable    3
    FOR    ${i}    IN RANGE    0    ${retries}
        Notify failure    retries=${retries}
    END

The retries should only be interpreted when raising the incidenrt the first time. After that count down the retries internally and ignore the retries argument.