sbox: print more errors

The output directory is deleted, so when I want to
see the files there, it can really be helpful to
see more.

Bug: N/A
Test: N/A
Change-Id: Ie40c412fe1bebbf87db00a4dbce107696ab2805e
diff --git a/cmd/sbox/sbox.go b/cmd/sbox/sbox.go
index 91e3540..fc56dd5 100644
--- a/cmd/sbox/sbox.go
+++ b/cmd/sbox/sbox.go
@@ -390,7 +390,7 @@
 		}
 	}
 
-	const maxErrors = 10
+	const maxErrors = 25
 
 	if len(incorrectOutputDirectoryErrors) > 0 {
 		errorMessage := ""