Restore array indentation

Seems like the INDENT_ARRAYS_WITH_INDICATOR (compared to plain
INDENT_ARRAYS) option doesn't have the problem that it generates

array:
  -
    aa: bb

but rather

array:
  - aa: bb

as expected. But also the Paper dependency format looks different now
so there is nothing weird generated anyway.

Author: stephan-gh

src/main/kotlin/net/minecrell/pluginyml/GeneratePluginDescription.kt

@@ -70,6 +70,7 @@ abstract class GeneratePluginDescription : DefaultTask() {
             .disable(YAMLGenerator.Feature.WRITE_DOC_START_MARKER)
             .enable(YAMLGenerator.Feature.MINIMIZE_QUOTES)
             .enable(YAMLGenerator.Feature.ALWAYS_QUOTE_NUMBERS_AS_STRINGS)
+            .enable(YAMLGenerator.Feature.INDENT_ARRAYS_WITH_INDICATOR)
 
         val module = SimpleModule()
         @Suppress("UNCHECKED_CAST") // Too stupid to figure out the generics here...