patch 9.1.0989: Vim9: Whitespace after the final enum value causes a syntax error

Problem:  Vim9: Whitespace after the final enum value causes a syntax
          error
Solution: Fix parsing to allow whitespace after the final enum value.
          (Doug Kearns)

closes: #16383

Signed-off-by: Doug Kearns <dougkearns@gmail.com>
Signed-off-by: Yegappan Lakshmanan <yegappan@yahoo.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>

src/testdir/test_vim9_enum.vim

@@ -908,6 +908,18 @@ def Test_enum_comments()
   END
   v9.CheckSourceSuccess(lines)
 
+  lines =<< trim END
+    vim9script
+    enum Car   # cars
+      # before enum
+      Honda(), # honda
+      # before enum
+      Ford()   # ford
+    endenum
+    assert_equal(1, Car.Ford.ordinal)
+  END
+  v9.CheckSourceSuccess(lines)
+
   # Test for using an unsupported comment
   lines =<< trim END
     vim9script
@@ -921,6 +933,29 @@ def Test_enum_comments()
   v9.CheckSourceFailure(lines, 'E1170: Cannot use #{ to start a comment', 4)
 enddef
 
+" Test trailing whitespace after enum values
+def Test_enum_whitespace()
+  var lines =<< trim END
+    vim9script
+    enum Car
+      Honda, 
+      Ford   
+    endenum
+    defcompile
+  END
+  v9.CheckSourceSuccess(lines)
+
+  lines =<< trim END
+    vim9script
+    enum Car
+      Honda(), 
+      Ford()   
+    endenum
+    defcompile
+  END
+  v9.CheckSourceSuccess(lines)
+enddef
+
 " Test string() with enums
 def Test_enum_string()
   var lines =<< trim END