Regex for type milestoneID not allowing spaces in milestoneID

[loro2]

Github does allow spaces in milestone ids, the pattern validation in Zerocracy breaks in such cases, see https://github.com/zerocracy/farm/issues/2051

File: /xsd/pm/time/types.xsd

[0crat]

@g4s8/z please, pay attention to this issue

[g4s8]

@0crat assign me

[0crat]

@0crat assign me (here)

@g4s8 @g4s8/z not enough funds available in the project, can't set budget of job #409, see §21; @g4s8/z will get no money on completion; in order to fix that, add funds to the project and assign the job again

[0crat]

Manual assignment of issues is discouraged, see §19: -5 point(s) just awarded to @g4s8/z

[0crat]

Bug was reported, see §29: +15 point(s) just awarded to @loro2/z