Fix IPFS-hash workflow build failure from missing Tailscale image tag

[Copilot]

The Build and post IPFS hash GitHub Actions job failed because the build referenced a non-existent upstream image tag (tailscale/tailscale:v1.98.5). This PR repoints the package to an available upstream tag so the CI build step can resolve its base image.

• Root cause

  • CI build pulled tailscale/tailscale:v1.98.5, which is not published on Docker Hub.

• Change

  • Downgraded the pinned upstream Tailscale version from v1.98.5 to v1.98.4 in:
    • dappnode_package.json (upstreamVersion)
    • docker-compose.yml (build.args.UPSTREAM_VERSION)

• Impact

  • Keeps Dockerfile/image resolution aligned with a published upstream tag used by the workflow build path.

# docker-compose.yml
services:
  tailscale:
    build:
      args:
        UPSTREAM_VERSION: v1.98.4