How to checkout a branch (and not a tag)

[Jeffrey Walton <noloader@xxxxxxxxx>]

I'm trying to checkout a branch called REL1_35 from
https://github.com/wikimedia/mediawiki-skins-Cosmos. The repo also has
a tag called REL1_35.

When I perform the following I apparently get the tag (with old files)
and not the branch (with updated files):

    wiki_rel=REL1_53
    ...
    git fetch origin && git reset --hard "origin/${wiki_rel}" && \
        git checkout -f "${wiki_rel}" && git pull && git clean -xdf

I found https://groups.google.com/g/git-users/c/FfzGmqj6sNQ, but I am
not following it. My .git/config looks like it is using the proper
reference:

# cat skins/Cosmos/.git/config
[core]
        repositoryformatversion = 0
        filemode = true
        bare = false
        logallrefupdates = true
[remote "origin"]
        url = https://github.com/Universal-Omega/MediaWiki-Cosmos-skin.git
        fetch = +refs/heads/*:refs/remotes/origin/*
[branch "REL1_35"]
        remote = origin
        merge = refs/heads/REL1_35

How do I checkout the branch (and not a tag)?

Thanks in advance.