Add explicit return types to several test data files so that AST access is not needed

Test cases are chosen so that addition/removal of explicit type will not interfere with the original purpose of the test

compiler/testData/loadJava/compiledKotlin/prop/defaultAccessors/ClassVarModality.kt

@@ -1,14 +1,14 @@
 package test
 
 open class ClassVarModality() {
-    open var property1 = 1
+    open var property1: Int = 1
 
-    final internal var property2 = 1
+    final internal var property2: Int = 1
 
-    open var property3 = 1
+    open var property3: Int = 1
       private set
 
-    final internal var property4 = 1
+    final internal var property4: Int = 1
       private  set
 }