doc: a few small fixes

Change-Id: Ia0c73d82feb6c736fbaf031c8ed95a43e923fe59
Reviewed-on: https://cue-review.googlesource.com/c/1540
Reviewed-by: Marcel van Lohuizen <mpvl@google.com>
diff --git a/doc/ref/spec.md b/doc/ref/spec.md
index 6292616..71efed3 100644
--- a/doc/ref/spec.md
+++ b/doc/ref/spec.md
@@ -436,7 +436,7 @@
 ```
 
 Carriage return characters (`\r`) inside string literals are discarded from
-the raw string value.
+the string value.
 
 ```
 'a\000\xab'