Fix useless "Remove curly braces" before Chinese character

So #KT-20409 Fixed

idea/testData/quickfix/removeToStringInStringTemplate/necessaryBrackets1.kt

@@ -0,0 +1,4 @@
+// "Remove 'toString()' call" "true"
+
+val foo = "test"
+val bar = "${foo.toString()<caret>}_"

idea/testData/quickfix/removeToStringInStringTemplate/necessaryBrackets1.kt.after

@@ -0,0 +1,4 @@
+// "Remove 'toString()' call" "true"
+
+val foo = "test"
+val bar = "${foo<caret>}_"

idea/testData/quickfix/removeToStringInStringTemplate/necessaryBrackets2.kt

@@ -0,0 +1,4 @@
+// "Remove 'toString()' call" "true"
+
+val foo = "test"
+val bar = "${foo.toString()<caret>}コトリン"

idea/testData/quickfix/removeToStringInStringTemplate/necessaryBrackets2.kt.after

@@ -0,0 +1,4 @@
+// "Remove 'toString()' call" "true"
+
+val foo = "test"
+val bar = "${foo<caret>}コトリン"