UAST: Complex test data moved to separate file (KT-20990)

plugins/uast-kotlin/testData/StringTemplateComplex.kt

@@ -0,0 +1,17 @@
+val muchRecur = "${"${"${"abc"}"}"}"
+
+val case4 = "a ${"literal"} z"
+
+val case5 = "a ${"literal"} ${"literal"} z"
+
+val literalInLiteral = "a ${"literal$case4"} z"
+
+val literalInLiteral2 = "a ${"literal$case4".repeat(4)} z"
+
+fun simpleForTemplate(i: Int = 0) = "$i"
+
+fun foo() {
+    println("$baz")
+    val template1 = "${simpleForTemplate()}"
+    val template2 = ".${simpleForTemplate()}"
+}