[librsvg] Sigh, also sudo for "cargo doc"

[Federico Mena Quintero <federico src gnome org>]

commit 7e6c8e30f40a3868ceb9dad48337e66508010149
Author: Federico Mena Quintero <federico gnome org>
Date:   Thu Jun 11 12:47:25 2020 -0500

    Sigh, also sudo for "cargo doc"

 .gitlab-ci.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index a44df5f0..54214be1 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -236,7 +236,7 @@ pages:
   stage: test
   script:
     - mkdir -p public/doc
-    - cargo doc --document-private-items --no-deps
+    - sudo cargo doc --document-private-items --no-deps
     - cp -r target/doc/* public/doc
 
   artifacts: