fix(ci): use DEV registry password for DEV registry login in prod build

[duckhawk]

Description

The prod build (.github/workflows/build_prod.yml) has two modules-actions/setup@v4 login steps per job: the first logs into the PROD registry, the second into the DEV registry (registry: ${{ vars.DEV_REGISTRY }}, registry_login: ${{ vars.DEV_MODULES_REGISTRY_LOGIN }}).

The second (DEV) step was passing the PROD password:

registry_password: ${{ secrets.PROD_MODULES_REGISTRY_PASSWORD }}   # wrong for the DEV registry

This changes it back to the DEV password in all editions (ce/ee/fe/se/se-plus):

registry_password: ${{ secrets.DEV_MODULES_REGISTRY_PASSWORD }}

The build step keeps the PROD credentials — those are correct because module_source points to the PROD registry.

Why do we need it, and what problem does it solve?

The mismatch was introduced together with the VEX attestation change. Logging into the DEV registry with the PROD password fails (werf cr login … unauthorized: Auth failed), which breaks the prod build for every edition on tag builds. The DEV registry is the secondary_repo push target, so a valid DEV login is required.

The same defect was observed and fixed in csi-ceph (deckhouse/csi-ceph#189), where it broke the v0.5.30 release build.

What is the expected result?

A tagged prod build logs into both the PROD and DEV registries successfully and builds/pushes the module images for every edition.

Checklist

• The code is covered by unit tests.
• e2e tests passed.
• Documentation updated according to the changes.
• Changes were tested in the Kubernetes cluster manually.