Fix script/benchstat-ratio.go when there's no '/'
diff --git a/script/benchstat-ratio.go b/script/benchstat-ratio.go
index 50bcd12..0925b44 100644
--- a/script/benchstat-ratio.go
+++ b/script/benchstat-ratio.go
@@ -192,7 +192,7 @@
 	}
 	j := strings.IndexByte(key[i:], '/')
 	if j < 0 {
-		return ""
+		j = len(key) - i
 	}
 	return key[:1] + *baseline + key[i:i+j] + gccSuffix
 }