[epiphany] ci: Set safe.directory for the GTK4 checkout

[Alexander Mikhaylenko <alexm src gnome org>]

commit 5472fa06122dd788155ffbd1d060b36ec885ff52
Author: Alexander Mikhaylenko <alexm gnome org>
Date:   Wed Oct 12 23:49:01 2022 +0400

    ci: Set safe.directory for the GTK4 checkout
    
    Git doesn't like that anymore, so work around it.

 .gitlab-ci.yml | 1 +
 1 file changed, 1 insertion(+)
---
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index f09d61fc3..e7a88fddc 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -99,6 +99,7 @@ flatpak master gtk3:
 flatpak master:
   extends: '.flatpak'
   before_script:
+    - git config --add safe.directory .
     - git checkout wip/exalm/gtk4
   variables:
     CONFIG_OPTS: '-Dtech_preview=true -Dprofile=Devel -Dunit_tests=enabled -Dgsb_api_key=${GSB_API_KEY}'