KT-44043 [Sealed interfaces]: tests

So far, quick-fix tests infrastructure neither supports the check
for multiple files (several .before/.after pairs) nor multi module
structure. Provided tests are quite limited yet allow to make sure that
the fix in question appears in expected context and get activated.

^KT-44043 fixed

idea/testData/quickfix/moveToSealedParent/nestedDeclarationToSealed.test

@@ -0,0 +1,27 @@
+// FILE: DerivedOutsideOfPackage.before.kt
+// "Move Derived to the package/module of SomeSealedClass" "true"
+// ERROR: Inheritor of sealed class or interface declared in package <root> but it must be in package foo where base class is declared
+// COMPILER_ARGUMENTS: -XXLanguage:+SealedInterfaces -XXLanguage:+AllowSealedInheritorsInDifferentFilesOfSamePackage
+
+import foo.SomeSealedClass
+
+class ArbitraryClass {
+    class Derived: <caret>SomeSealedClass()
+}
+
+
+// FILE: foo/SealedDeclarations.kt
+package foo
+
+sealed class SomeSealedClass
+
+
+// FILE: DerivedOutsideOfPackage.after.kt
+// "Move Derived to the package/module of SomeSealedClass" "true"
+// ERROR: Inheritor of sealed class or interface declared in package <root> but it must be in package foo where base class is declared
+// COMPILER_ARGUMENTS: -XXLanguage:+SealedInterfaces -XXLanguage:+AllowSealedInheritorsInDifferentFilesOfSamePackage
+
+class ArbitraryClass {
+<caret>}
+
+

idea/testData/quickfix/moveToSealedParent/topLevelDeclarationToSealed.test

@@ -0,0 +1,27 @@
+// FILE: DerivedOutsideOfPackage.before.kt
+// "Move Derived to the package/module of SomeSealedClass" "true"
+// ERROR: Inheritor of sealed class or interface declared in package <root> but it must be in package foo where base class is declared
+// COMPILER_ARGUMENTS: -XXLanguage:+SealedInterfaces -XXLanguage:+AllowSealedInheritorsInDifferentFilesOfSamePackage
+
+import foo.SomeSealedClass
+
+class Derived: <caret>SomeSealedClass()
+class ArbitraryClass
+
+
+// FILE: foo/SealedDeclarations.kt
+package foo
+
+sealed class SomeSealedClass
+
+
+// FILE: DerivedOutsideOfPackage.after.kt
+// "Move Derived to the package/module of SomeSealedClass" "true"
+// ERROR: Inheritor of sealed class or interface declared in package <root> but it must be in package foo where base class is declared
+// COMPILER_ARGUMENTS: -XXLanguage:+SealedInterfaces -XXLanguage:+AllowSealedInheritorsInDifferentFilesOfSamePackage
+
+import foo.SomeSealedClass
+
+<caret>class ArbitraryClass
+
+