Update io.forward/yaml dependency.

[justone]

With 1.0.9, I was getting the errors from owainlewis/yaml#28.

[brosenan]

Travis seems to not like this change. The error message seems related to this change:

LOAD FAILURE for lambdakube.core-test

clojure.lang.Compiler$CompilerException: java.lang.UnsupportedClassVersionError: org/yaml/snakeyaml/constructor/PassthroughConstructor has been compiled by a more recent version of the Java Runtime (class file version 55.0), this version of the Java Runtime only recognizes class file versions up to 53.0, compiling:(yaml/reader.clj:1:1)

 java.lang.UnsupportedClassVersionError: org/yaml/snakeyaml/constructor/PassthroughConstructor has been compiled by a more recent version of the Java Runtime (class file version 55.0), this version of the Java Runtime only recognizes class file versions up to 53.0

Please figure out the conflict (probably some other dependencies that need to be upgraded) and try again.

Thanks,
Boaz.

[justone]

Looks like the trick was updating to JDK 11 and the latest version of Midje. Each of those solved a different issue. I also bumped the remaining versions to latest.