fix: fetch full git history for GoReleaser to correctly push latest tag

[Bhagwat-45]

Problem

Fixes #4087

The latest Docker tag for redpandadata/connect has been stuck on 4.67.5 since October 2025. Subsequent releases (4.68.0 through 4.87.0+) built successfully but never updated the latest tag on Docker Hub or ECR.

Root Cause

The release workflow was checking out the repository with the default shallow clone (fetch-depth: 1). GoReleaser requires full git history to correctly parse tag metadata and evaluate its template variables.

This was visible in the GoReleaser release logs as an explicit warning:

• couldn't find any tags before "v4.87.0"
• running against a shallow clone - check your CI documentation at https://goreleaser.com/ci

With an incomplete git history, GoReleaser cannot correctly resolve .Prerelease from the tag context, causing the latest tag template in .goreleaser/connect.yaml to silently evaluate to an empty string and be skipped entirely:

- "{{ if and (not .IsSnapshot) (eq .Prerelease ``) }}latest{{ end }}"

As a result, only versioned tags (4.87.0, 4.87, 4) were pushed — never latest.

Fix

Add fetch-depth: 0 and fetch-tags: true to the checkout step in the release workflow so GoReleaser has the full git history it needs to correctly evaluate tag templates.

- name: Check Out Repo
  uses: actions/checkout@v6
  with:
    fetch-depth: 0
    fetch-tags: true

Testing

The next stable release after this fix should show latest appearing in the GoReleaser publishing logs alongside the versioned tags, and docker pull redpandadata/connect:latest should return the most recent version.

[CLAassistant]

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