Add workflow for update flake.lock

.gitlab-ci.yml

@@ -2,22 +2,12 @@ default:
   tags:
     - nix
 
-stages:
-  - build
+include:
+  - local: .gitlab-ci/build.yml
+    rules:
+      - if: $CI_PIPELINE_SOURCE == "push"
+  - local: .gitlab-ci/update.yml
+    rules:
+      - if: $CI_PIPELINE_SOURCE == "schedule"
 
-build-nixos-configurations:
-  stage: build
-  parallel:
-    matrix:
-      - HOST_TO_BUILD:
-          - kharbranth
-          - kholinar
-          - lasting-integrity
-          - urithiru
-  script:
-    - nix-env --quiet -j8 -iA cachix -f https://cachix.org/api/v1/install
-    - cachix --version
-    - cachix authtoken $CACHIX_AUTH_TOKEN
-    - nix build -L --no-link .#nixosConfigurations.${HOST_TO_BUILD}.config.system.build.toplevel
-    - nix eval --json .#nixosConfigurations.${HOST_TO_BUILD}.config.system.build.toplevel | sed 's/"\(.*\)"/\1/' | cachix push chvp