Psi2ir: ignore unresolved annotations

Note that the test is an exact copy of an existing test
missingDependencyNestedAnnotation, but with -Xuse-ir

compiler/ir/ir.psi2ir/src/org/jetbrains/kotlin/psi2ir/generators/AnnotationGenerator.kt

@@ -40,7 +40,7 @@ class AnnotationGenerator(context: GeneratorContext) : IrElementVisitorVoid {
                 declaration.descriptor.backingField
             else declaration.descriptor
 
-        annotatedDescriptor?.annotations?.mapTo(declaration.annotations) {
+        annotatedDescriptor?.annotations?.mapNotNullTo(declaration.annotations) {
             constantValueGenerator.generateAnnotationConstructorCall(it)
         }
     }

compiler/ir/ir.psi2ir/src/org/jetbrains/kotlin/psi2ir/generators/ModuleGenerator.kt

@@ -73,7 +73,7 @@ class ModuleGenerator(override val context: GeneratorContext) : Generator {
 
         for (ktAnnotationEntry in ktFile.annotationEntries) {
             val annotationDescriptor = getOrFail(BindingContext.ANNOTATION, ktAnnotationEntry)
-            irFile.annotations.add(constantValueGenerator.generateAnnotationConstructorCall(annotationDescriptor))
+            irFile.annotations.addIfNotNull(constantValueGenerator.generateAnnotationConstructorCall(annotationDescriptor))
         }
 
         for (ktDeclaration in ktFile.declarations) {