Add rackunit-doc to build-deps.

info.rkt

@@ -2,6 +2,6 @@
 (define collection "txexpr")
 (define deps '("base" "sugar" "rackunit-lib"))
 (define update-implies '("sugar"))
-(define build-deps '("scribble-lib" "racket-doc"))
+(define build-deps '("scribble-lib" "racket-doc" "rackunit-doc"))
 (define scribblings '(("scribblings/txexpr.scrbl" ())))
-(define compile-omit-paths '("tests.rkt"))
+(define compile-omit-paths '("tests.rkt"))