gh-622: add note about unique constraint for release v1.17.28
gh-622: add note about unique constraint for release v1.17.28

liimaorg/liima,liimaorg/liima,liimaorg/liima,liimaorg/liima,liimaorg/liima,liimaorg/liima,liimaorg/liima,liimaorg/liima