"Unused equals expression" inspection: highlight whole expression with yellow background

^KT-41615 Fixed

idea/testData/inspectionsLocal/unusedEquals/.inspection

@@ -0,0 +1 @@
+org.jetbrains.kotlin.idea.inspections.UnusedEqualsInspection

idea/testData/inspectionsLocal/unusedEquals/equals.kt

@@ -0,0 +1,4 @@
+// FIX: none
+fun foo(a: Int, b: Int) {
+    <caret>a.equals(b)
+}

idea/testData/inspectionsLocal/unusedEquals/equals2.kt

@@ -0,0 +1,4 @@
+// FIX: none
+fun foo(a: Int, b: Int) {
+    a.equals(b)<caret>
+}

idea/testData/inspectionsLocal/unusedEquals/simple.kt

@@ -0,0 +1,4 @@
+// FIX: none
+fun foo(a: Int, b: Int) {
+    <caret>a == b
+}

idea/testData/inspectionsLocal/unusedEquals/simple2.kt

@@ -0,0 +1,4 @@
+// FIX: none
+fun foo(a: Int, b: Int) {
+    a == b<caret>
+}