Breaking changes in ktfmt 0.31

[msfjarvis]

ktfmt 0.31 was just released which includes a couple breaking changes for Spotless. Specifically

• Library usage was updated to make the format method no longer be a top-level method. It is now inside the Formatter object.
• The binaries for 0.31 appear to have been published to Maven Central's new S01 infrastructure, which means the dependency needs to be resolved from https://repo1.maven.org/maven2 as opposed to https://repo.maven.org/maven2.

I'm not super familiar with reflection so it might take me a day or two before I can propose a PR for at least the first part of this. Let me know if you'd prefer to do it yourself faster.

[nedtwigg]

PR is very welcome, I've got no plans to integrate these changes. If you'd like, you can avoid reflection entirely by following an example from #524. Could do if (version < 31) { existingCode() } else { newCode() }

[msfjarvis]

Oh that looks much easier, I will try that approach out. Thanks a lot!

[nedtwigg]

Fixed in plugin-gradle 6.2.2 and plugin-maven 2.20.2.