Extract common logic for annotation entries collection

Before this change annotation entries starting with '@' within expressions hadn't been resolved

Note that order of annotation entries in result may change according to order of children in PSI (see changed testData)

compiler/testData/diagnostics/tests/annotations/atAnnotationResolve.kt

@@ -0,0 +1,14 @@
+// !DIAGNOSTICS: -UNUSED_PARAMETER
+annotation class Ann(val x: Int = 6)
+
+@Ann(1) [Ann(2)] @Ann(3) @private class A [Ann] () {
+    @Ann(x = 5) fun foo() {
+        1 + @Ann(1) 1 * @Ann(<!TYPE_MISMATCH!>""<!>) 6
+
+        @Ann fun local() {}
+    }
+
+    @Ann val x = 1
+
+    fun bar(x: @Ann(1) [Ann(2)] @Ann(3) Int) {}
+}