gh-35417: Remove tag fetching in docker workflow
    
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### 📚 Description

It fails in forks (e.g. https://github.com/tobiasdiez/sage/actions/runs/
4586854543/jobs/8100123316) and shouldn't be necessary since the tag
will be passed anyway via `EXTRA_DOCKER_TAGS`.

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URL: #35417
Reported by: Tobias Diez
Reviewer(s): Matthias Köppe

Author: Release Manager

.github/workflows/docker.yml

@@ -147,8 +147,6 @@ jobs:
           repository: ${{ inputs.sage_repo }}
           ref: ${{ inputs.sage_ref }}
           fetch-depth: 10000
-      - name: fetch tags
-        run: git fetch --depth=1 origin +refs/tags/*:refs/tags/*
       - name: free disk space
         run: |
           df -h