[gimp-web/oscp] testing.developer: Fix tag name

[Bartłomiej Piotrowski <bpiotrowski src gnome org>]

commit bf37a09af3468aed31c14aa6e695ea89583d1a5f
Author: Bartłomiej Piotrowski <bpiotrowski gnome org>
Date:   Tue May 24 16:09:39 2022 +0200

    testing.developer: Fix tag name

 .gitlab-ci.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index cc75e0b9..550afe6b 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -31,7 +31,7 @@ testing.developer.gimp.org:
   extends:
     - .build
   variables:
-    OCI_TAG: testing+developer
+    OCI_TAG: testing_developer
 
 static.gimp.org:
   extends: