Tests fail on Python 3.5 because dicts are unordered

[cclauss]

https://github.com/micheles/decorator/runs/2311776691

File "/home/runner/work/decorator/decorator/src/tests/documentation.py", line 496, in documentation
Failed example:
    printsum2(y=2, x=1)
Expected:
    () {'y': 2, 'x': 1}
    3
Got:
    () {'x': 1, 'y': 2}
    3

[micheles]

I know, fixed in c8fed19