Reduce the logging level from `WARN` to `INFO` when reporting applied version of CoreJvm Compiler

[alexander-yevsyukov]

See McJavaPlugin.kt and Project.logApplying() extension function for details.

It was WARN level to closerly monitor the applied version during the development and integration tests without enabling the INFO level manually.

Normally, this kind of logging should be at INFO level. Let's adjust it closer to the release of v2.0.

[alexander-yevsyukov]

Let's keep it reported at the current level. We'll reduce the noice after v2.0.0 is officially out and applied to current clients of v1.x.