Do not use enum for annotation_level

Author: tinybeachthor

src/diff.ts

@@ -82,7 +82,7 @@ export default async function generateAnnotations (edited: types.File, original:
       path: original.filename,
       start_line: oldStart,
       end_line: oldStart + oldLines,
-      annotation_level: types.AnnotationLevel.Failure,
+      annotation_level: 'failure',
       message: `Lines ${oldStart}-${oldStart+oldLines} need formatting.`,
     })
     return {

src/types.d.ts

@@ -7,17 +7,11 @@ declare module types {
     newLines: number
   }
 
-  enum AnnotationLevel {
-    Failure = 'failure',
-    Warning = 'warning',
-    Infor = 'info',
-  }
-
   interface Annotation {
     path: string
     start_line: number
     end_line: number
-    annotation_level: AnnotationLevel
+    annotation_level: string
     message: string
   }