Use check=true for ktlint checkFormatAll run (#4247)

Fix small typo made in #4201 -
`checkFormalAll` task should fail in case of formatting violations.

Co-authored-by: 0xnm <[email protected]>

Author: 0xnm

kotlinlib/src/mill/kotlinlib/ktlint/KtlintModule.scala

@@ -87,7 +87,7 @@ object KtlintModule extends ExternalModule with KtlintModule with TaskModule {
         Tasks.resolveMainDefault("__.sources")
   ): Command[Unit] = Task.Command {
     ktlintAction(
-      KtlintArgs(format = false, check = false),
+      KtlintArgs(format = false, check = true),
       T.sequence(sources.value)().flatten,
       ktlintConfig(),
       ktlintOptions(),