[FIR-TEST] Add new testdata generated after changes in previous commit

compiler/testData/diagnostics/tests/override/ParentInheritsManyImplementations.fir.kt

@@ -0,0 +1,17 @@
+package d
+
+interface A {
+    fun foo() = 1
+}
+
+interface B {
+    fun foo() = 2
+}
+
+open class C : A, B {}
+
+interface E {
+    fun foo(): Int
+}
+
+class D : C() {}