Random.participantGroupName(): make the generated names conform to the validation rules

[0pdd]

The puzzle 738-13880c1a from #738 has to be resolved:

mystamps/src/test/java/ru/mystamps/web/tests/Random.java

Lines 152 to 153 in cf895bb

	// @todo #738 Random.participantGroupName(): make the generated names conform to
	// the validation rules (when they will appear)

The puzzle was created by Slava Semushin on 18-Jul-18.