Grammar correction

Closes spring-projectsgh-2262

spring-boot-docs/src/main/asciidoc/documentation-overview.adoc

@@ -30,7 +30,7 @@ Having trouble with Spring Boot, We'd like to help!
 
 * Try the <<howto.adoc#howto, How-to's>> -- they provide solutions to the most common
   questions.
-* Learn the Spring basics -- Spring Boot is builds on many other Spring projects, check
+* Learn the Spring basics -- Spring Boot builds on many other Spring projects, check
   the http://spring.io[spring.io] web-site for a wealth of reference documentation. If
   you are just starting out with Spring, try one of the http://spring.io/guides[guides].
 * Ask a question - we monitor http://stackoverflow.com[stackoverflow.com] for questions