Test for KT-7222 Redundant boxing on toString call

#KT-7222 Fixed

compiler/testData/codegen/bytecodeText/stringOperations/primitiveToString.kt

@@ -0,0 +1,14 @@
+fun main() {
+    false.toString()
+    1.toByte().toString()
+    1.toShort().toString()
+    1.toString()
+    1L.toString()
+    1.0F.toString()
+    1.0.toString()
+    'c'.toString()
+}
+
+/*Check that all "valueOf" are String ones and there is no boxing*/
+// 8 valueOf
+// 8 INVOKESTATIC java/lang/String.valueOf

compiler/tests/org/jetbrains/kotlin/codegen/BytecodeTextTestGenerated.java

@@ -687,6 +687,12 @@ public class BytecodeTextTestGenerated extends AbstractBytecodeTextTest {
             String fileName = JetTestUtils.navigationMetadata("compiler/testData/codegen/bytecodeText/stringOperations/plusAssign.kt");
             doTest(fileName);
         }
+
+        @TestMetadata("primitiveToString.kt")
+        public void testPrimitiveToString() throws Exception {
+            String fileName = JetTestUtils.navigationMetadata("compiler/testData/codegen/bytecodeText/stringOperations/primitiveToString.kt");
+            doTest(fileName);
+        }
     }
 
     @TestMetadata("compiler/testData/codegen/bytecodeText/when")