chore: add prepare stage for jsonp

.gitlab-ci.yml

 image: durcheinander/pack-build:1.1.0
 
 stages:
+- prepare
 - build
 - release
 
+prepare:
+  stage: prepare
+  rules:
+    - if: $CI_PIPELINE_SOURCE == "schedule"
+      when: never
+    - if: $CI_PIPELINE_SOURCE == "merge_request_event"
+    - if: $CI_COMMIT_TAG
+    - exists:
+      - resources
+  script:
+    - to-static-jsonp --fn hd resources/* -o .
+  artifacts:
+    paths:
+      - '*.js'
+
 build:
   image: durcheinander/export-apkgs:2.0.0
   stage: build