toYaml - Fixes #3410 - trailing \n issue

`toYaml` utilized by `.Files` was introducing a new line. It is an issue since the new line is part of a functions output, it can't be whitespace chomped away so it would require a `trimSuffix "\n"` pipe. This commit trims one trailing `\n` from the toYaml output.

(cherry picked from commit 35132d141c)

pkg/chartutil/files.go

@@ -175,7 +175,7 @@ func ToYaml(v interface{}) string {
 		// Swallow errors inside of a template.
 		return ""
 	}
-	return string(data)
+	return strings.TrimSuffix(string(data), "\n")
 }
 
 // FromYaml converts a YAML document into a map[string]interface{}.