chore(gitlab-ci): restructure based on stages

.gitlab-ci.yml

@@ -109,6 +109,20 @@ frontend lint:
   retry: 2
   interruptible: true
 
+backend lint:
+  stage: lint
+  cache:
+    - *stack-cache
+  script:
+    - "nix shell .#gnumake .#stack --command make CI=1 backend-lint"
+  before_script: *nix-before
+  needs:
+    - job: backend dependencies
+      artifacts: true
+  retry: 2
+  interruptible: true
+
+
 frontend build:
   stage: build
   cache:
@@ -135,19 +149,6 @@ frontend build:
   retry: 2
   interruptible: true
 
-backend lint:
-  stage: lint
-  cache:
-    - *stack-cache
-  script:
-    - "nix shell .#gnumake .#stack --command make CI=1 backend-lint"
-  before_script: *nix-before
-  needs:
-    - job: backend dependencies
-      artifacts: true
-  retry: 2
-  interruptible: true
-
 backend build:
   stage: build
   cache: