JavaCompletionUtil: do not add an unnecessary cast if hierarchy signature has several levels

Fixes IDEA-185554 Redundant cast on autocompletion

java/java-tests/testData/codeInsight/completion/normal/NoUnnecessaryCastDeepHierarchy.java

@@ -0,0 +1,18 @@
+class MyTest {
+    interface Container<K, V> {
+        V read(K k);
+    }
+
+    interface Container2<K, V> extends Container<K, V> {
+        V read(K k);
+    }
+
+    interface Container3<K, V> extends Container2<K, V> {
+        V read(K k);
+    }
+
+    void test(Container3<String, String> c3) {
+        Container<String, String> c = c3;
+        c.re<caret>
+    }
+}

java/java-tests/testData/codeInsight/completion/normal/NoUnnecessaryCastDeepHierarchy_after.java

@@ -0,0 +1,18 @@
+class MyTest {
+    interface Container<K, V> {
+        V read(K k);
+    }
+
+    interface Container2<K, V> extends Container<K, V> {
+        V read(K k);
+    }
+
+    interface Container3<K, V> extends Container2<K, V> {
+        V read(K k);
+    }
+
+    void test(Container3<String, String> c3) {
+        Container<String, String> c = c3;
+        c.read()
+    }
+}