`idempotent-attribute-is-not-first` lint should not label as CRITICAL

[maxonfjvipon]

Let's change error level from CRITICAL to WARNING
Motivation 1: objectionary/jeo-maven-plugin#1366 (comment)
Motivation 2: idempotentancy is a feature of EO only, but XMIR is IR which can be generated by many other way besides EO parsing and if it does not violate XSD scheme - it's perfectly valid

[yegor256]

@rultor release, tag is 0.0.60

[rultor]

@rultor release, tag is 0.0.60

@yegor256 OK, I will release it now. Please check the progress here.

[rultor]

@rultor release, tag is 0.0.60

@maxonfjvipon @yegor256 Oops, I failed. You can see the full log here (spent 2hr).

Docker container objectionary_lints_776 is lost

[maxonfjvipon]

@yegor256 let's try to release one more time

[h1alexbel]

@maxonfjvipon can we close this one?