Replace test assertions in the prod code with require

compiler/frontend/src/org/jetbrains/kotlin/psi/psiUtil/ktPsiUtil.kt

@@ -37,7 +37,7 @@ import org.jetbrains.kotlin.resolve.calls.callUtil.getResolvedCall
 import org.jetbrains.kotlin.resolve.calls.model.ArgumentMatch
 import org.jetbrains.kotlin.types.expressions.OperatorConventions
 import java.util.*
-import kotlin.test.assertTrue
+import kotlin.text.Regex
 
 // NOTE: in this file we collect only Kotlin-specific methods working with PSI and not modifying it
 
@@ -226,7 +226,7 @@ public fun StubBasedPsiElementBase<out KotlinClassOrObjectStub<out KtClassOrObje
         }
     }
 
-    assertTrue(this is KtClassOrObject)
+    require(this is KtClassOrObject) { "it should be ${KtClassOrObject::class} but it is a ${this.javaClass.name}" }
 
     val stub = getStub()
     if (stub != null) {
@@ -438,4 +438,5 @@ fun checkReservedPrefixWord(sink: DiagnosticSink, element: PsiElement, word: Str
     KtPsiUtil.getPreviousWord(element, word)?.let {
         sink.report(Errors.UNSUPPORTED.on(it, message))
     }
-}
+}
+