[Analysis API] Migrate existing code fragment tests to the new API

analysis/analysis-api/testData/components/compilerFacility/compilation/codeFragments/simple.kt

@@ -1,3 +1,14 @@
+// MODULE: context
+
+// FILE: context.kt
 fun test() {
-    <caret>val x = 0
-}
+    <caret_context>val x = 0
+}
+
+
+// MODULE: main
+// MODULE_KIND: CodeFragment
+
+// FILE: fragment.kt
+// CODE_FRAGMENT_KIND: EXPRESSION
+2 + 2 * 2