Fix fixall title suffix

[Shane-XB-Qian]

clear the 'fix all' meaning:
1, actually it is a 'term' which the 'all' meant all safe fixes only.
2, somehow some '(unsafe)' marker e.g F841 maybe would not be added, vs adding 'all safe fixes' suffix to 'fix all' probably would be a more direct meaning title.

[jhossbach]

Setting the unsafe_fixes to true will not change the behaviour of the "Fix all" action, this is actually part of the specification.

I don't really have an opinion other than we would be the first to call it "Fix all (safe fixes)", but do we really need this? It is pointed out twice in the README, once in the configuration example and at the end.

[Shane-XB-Qian]

do we really need this?

I think yes, to me I am not the first time confused 'fix all' meaning, specifically when I chose that action, but it would may be actually do nothing (no safe fixed there actually).

…

-- shane.xb.qian

[Shane-XB-Qian]

"Fix all (all safe fixes)" "Fix all (only safe fixes)" "Fix all (safe fixes)" you can choose one.

…

-- shane.xb.qian

[Shane-XB-Qian]

@jhossbach please check again if ok to you.

[Shane-XB-Qian]

so is it ok to merge now?

1. as for the desc format, seems the lib code was like following:

    """Optional type.

    Optional[X] is equivalent to Union[X, None].
    """

there is no blank line before the close """

2. as for the checks_with_fixall var, perhaps it was to make it clean to read.

but anyway those should be not a big deal, let me know if still need something to modify, or you can help me refine it as well. thanks.