Fix incorrect markdown syntax in BUILD.md
Linewrap a really long while I'm in here.
@@ -24,4 +24,5 @@ go test ./...
# Canonical source on how to build
-The travis.yml file in the project provides the canonical source on how to build in case this file is not properly maintained.
\ No newline at end of file
+The travis.yml file in the project provides the canonical source on how to
+build in case this file is not properly maintained.
