hotfix: use locally built deps image in GHA

[whhe]

Summary

Ragflow has updated the ragflow_deps Docker image recently, and we should switch to using a locally built image to avoid errors caused by the image change.

Solution Description

Update the GHA to use locally built ragflow_deps docker image.

[Copilot]

Pull request overview

This PR updates GitHub Actions workflows to build the ragflow_deps Docker image locally instead of pulling it from an external registry, preventing potential errors from upstream image changes.

• Adds dependency preparation and building steps to both dev and release workflows
• Removes platform-specific conditionals in the release workflow, making dependency building apply to both amd64 and arm64 platforms
• Uses locally downloaded dependencies via download_deps.py to build the infiniflow/ragflow_deps:latest image

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
.github/workflows/release.yml	Removes arm64-specific conditionals and adds dependency preparation/building steps for all platforms
.github/workflows/dev.yml	Adds new dependency preparation and building steps before the main image build

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[CHLK]

LGTM