Fix incompatibility with JAnsi < 2.1.0

[Vankka]

This PR fixes JAnsiColorLevel reporting as available on < 2.1.0 where AnsiColors does not exist and AnsiConsole#out has a different signature 2.1.0 2.0.1

Error thrown when calling JAnsiColorLevel#compute on JAnsi < 2.1.0

java.lang.NoSuchMethodError: 'org.fusesource.jansi.AnsiPrintStream org.fusesource.jansi.AnsiConsole.out()'
        at net.kyori.ansi.JAnsiColorLevel.computeFromJAnsi(JAnsiColorLevel.java:50) ~[?:?]
        at net.kyori.ansi.ColorLevel.compute(ColorLevel.java:207) ~[?:?]
        at net.kyori.adventure.text.serializer.ansi.ANSIComponentSerializerImpl$BuilderImpl.<init>(ANSIComponentSerializerImpl.java:151) ~[?:?]
        at net.kyori.adventure.text.serializer.ansi.ANSIComponentSerializer.builder(ANSIComponentSerializer.java:63) ~[?:?]

[zml2008]

JAnsi 2.1.0 was released just about 4 years ago, but sure i guess