[CI] Publish build artifact via Pages

.gitlab-ci.yml

+image: rust:bullseye
+
 stages:
   - build
+  - publish
 
 build:
   stage: build
-  image: rust:bullseye
   before_script:
     - apt-get -y update
     - apt-get -y install gcc libjq-dev libonig-dev libpam0g-dev
@@ -13,3 +15,12 @@ build:
   artifacts:
     paths:
       - target/release/libnss_pam_webapi.so
+
+pages:
+    stage: publish
+    script:
+      - mkdir public
+      - cp target/release/libnss_pam_webapi.so public/
+    artifacts:
+      paths:
+        - public