Add annotation soft keyword as simple identifier

Author: punchagan

grammar.js

@@ -1108,7 +1108,8 @@ module.exports = grammar({
       "actual",
       "set",
       "get",
-      "enum"
+      "enum",
+      "annotation",
       // TODO: More soft keywords
     ),
 

test/corpus/expressions.txt

@@ -156,6 +156,8 @@ when {
   hasEnum() -> enum.loc.filename
 }
 
+annotations.filter { annotation -> true }
+
 --------------------------------------------------------------------------------
 
 (source_file
@@ -173,7 +175,20 @@ when {
             (navigation_suffix
               (simple_identifier)))
           (navigation_suffix
-            (simple_identifier)))))))
+            (simple_identifier))))))
+  (call_expression
+    (navigation_expression
+      (simple_identifier)
+      (navigation_suffix
+        (simple_identifier)))
+    (call_suffix
+      (annotated_lambda
+        (lambda_literal
+          (lambda_parameters
+            (variable_declaration
+              (simple_identifier)))
+          (statements
+            (boolean_literal)))))))
 
 ================================================================================
 Value declaration with receiver type