Trigger automatic line separator detection in tests

This is required when loading KtFile using standard methods

detekt-parser/src/test/kotlin/io/github/detekt/parser/KtCompilerSpec.kt

@@ -3,7 +3,6 @@ package io.github.detekt.parser
 import io.github.detekt.test.utils.resourceAsPath
 import org.assertj.core.api.Assertions.assertThat
 import org.assertj.core.api.Assertions.assertThatIllegalArgumentException
-import org.jetbrains.kotlin.com.intellij.psi.PsiErrorElement
 import org.jetbrains.kotlin.psi.KtTreeVisitorVoid
 import org.junit.jupiter.api.Nested
 import org.junit.jupiter.api.Test
@@ -20,13 +19,19 @@ class KtCompilerSpec {
  fun `Kotlin file with LF line separators has extra user data`() {
  val ktFile = ktCompiler.compile(path.resolve("DefaultLf.kt"))
 
+ // visit file to trigger line detection
+ ktFile.accept(KtTreeVisitorVoid())
+
  assertThat(ktFile.virtualFile.detectedLineSeparator).isEqualTo("\n")
  }
 
  @Test
  fun `Kotlin file with CRLF line separators has extra user data`() {
  val ktFile = ktCompiler.compile(path.resolve("DefaultCrLf.kt"))
 
+ // visit file to trigger line detection
+ ktFile.accept(KtTreeVisitorVoid())
+
  assertThat(ktFile.virtualFile.detectedLineSeparator).isEqualTo("\r\n")
  }