cleanup typo

[wbl]

This seems to have gotten dropped in some editorial passes

[bc-pi]

Upon consultation and review yesterday with the editors (@Sakurann, @danielfett and myself) agreed that we preferred the text omitting "the standard".

[wbl]

The current sentence reads "It does not meet security notations for anonymous credentials [@?CL01]." Probably a typo introduced by me, that should read notions. I'll assume we fix that. A reader is left wondering why the security notions it does not meet are relevant. There needs to be some indication of why these properties matter, and importantly that it cannot be dropped in where other schemes could be used.

(Maybe properties is clearer overall: I think we should change to that on reading this again)

[bc-pi]

The current sentence reads "It does not meet security notations for anonymous credentials [@?CL01]." Probably a typo introduced by me, that should read notions. I'll assume we fix that. A reader is left wondering why the security notions it does not meet are relevant. There needs to be some indication of why these properties matter, and importantly that it cannot be dropped in where other schemes could be used.

(Maybe properties is clearer overall: I think we should change to that on reading this again)

some possibilities suggested on the text