build unsigned release on every branch

.gitlab-ci.yml

-build-firefox-extension:
+build-firefox-extension-signed:
   image: node:lts
   before_script:
     - yarn global add web-ext
   script:
     - yarn install
-    - yarn build
+    - yarn build-src
     - yarn web-ext sign --api-key=${MOZ_API_KEY} --api-secret=${MOZ_API_SECRET} --id=${MOZ_GECKO_ID} -s src/
     - mv web-ext-artifacts/*.xpi ./url-shorter-xpi
-    - mv web-ext-artifacts/*.zip ./url-shorter-zip
   artifacts:
     paths:
       - public/url-shorter-xpi
-      - public/url-shorter-zip
   only:
-    - master
+    - master
\ No newline at end of file
+
+build-firefox-extension-unsigned:
+  image: node:lts
+  before_script:
+    - yarn global add web-ext
+  script:
+    - yarn install
+    - yarn build
+    - mv web-ext-artifacts/*.zip ./url-shorter-zip
+  artifacts:
+    paths:
+      - public/url-shorter-zip
\ No newline at end of file