KT-6582 "Expand selection" in string literal should select word in string

#KT-6582 fixed

idea/testData/wordSelection/SimpleStringLiteral2/0.kt

@@ -0,0 +1,3 @@
+fun main(args: Array<String>) {
+    println("<caret>foo bar")
+}

idea/testData/wordSelection/SimpleStringLiteral2/1.kt

@@ -0,0 +1,3 @@
+fun main(args: Array<String>) {
+    println("<selection><caret>foo</selection> bar")
+}

idea/testData/wordSelection/SimpleStringLiteral2/2.kt

@@ -0,0 +1,3 @@
+fun main(args: Array<String>) {
+    println("<selection><caret>foo bar</selection>")
+}

idea/testData/wordSelection/SimpleStringLiteral2/3.kt

@@ -0,0 +1,3 @@
+fun main(args: Array<String>) {
+    println(<selection>"<caret>foo bar"</selection>)
+}