Comment Color Brightness

-> Please see nordtheme/nord#94 for all
   details about this design change decision.

Increased the comment color (`nord3`) brightness by 10% from a lightness
level of ~35% to ~45%.

GH-6

src/Nord.xccolortheme

@@ -96,9 +96,9 @@ References
       <key>xcode.syntax.character</key>
       <string>0.574309 0.70253 0.464919 1</string>
       <key>xcode.syntax.comment</key>
-      <string>0.239159 0.263378 0.343876 1</string>
+      <string>0.307666 0.352597 0.459645 1</string>
       <key>xcode.syntax.comment.doc</key>
-      <string>0.239159 0.263378 0.343876 1</string>
+      <string>0.307666 0.352597 0.459645 1</string>
       <key>xcode.syntax.comment.doc.keyword</key>
       <string>0.506519 0.684472 0.678581 1</string>
       <key>xcode.syntax.identifier.class</key>