treewide: remove empty slice return value with nil

Change-Id: I36253a7f3c7d882175b90be34e685dde3e923521
Reviewed-on: https://review.monogon.dev/c/monogon/+/3043
Reviewed-by: Serge Bazanski <serge@monogon.tech>
Tested-by: Jenkins CI
diff --git a/build/bazel_cc_fix/main.go b/build/bazel_cc_fix/main.go
index 2e69110..ffd5edb 100644
--- a/build/bazel_cc_fix/main.go
+++ b/build/bazel_cc_fix/main.go
@@ -250,7 +250,7 @@
 	if len(entry.Arguments) == 0 {
 		commandArgs, err := shellwords.Parse(entry.Command)
 		if err != nil {
-			return []string{}, []string{}, fmt.Errorf("failed to parse command: %w", err)
+			return nil, nil, fmt.Errorf("failed to parse command: %w", err)
 		}
 		entry.Arguments = commandArgs
 	}