[buildbot] ci: fix missing tag on containers on git tag pushes

[LEDE Commits]

ynezz pushed a commit to buildbot.git, branch main:
https://git.openwrt.org/38f03c85e96155168dcbde5dedb3f83119511fe1

commit 38f03c85e96155168dcbde5dedb3f83119511fe1
Author: Petr Štetiar <ynezz at true.cz>
AuthorDate: Tue Jan 13 17:35:09 2026 +0100

    ci: fix missing tag on containers on git tag pushes
    
    Non semver tags like v26 were not included in metadata output, so image
    pushes only produced sha- tags. Add tag reference metadata so tag pushes
    publish a matching container tag.
    
      ##[warning]v26 is not a valid semver. More info: https://semver.org/
      ##[group]Docker tags
      ghcr.io/openwrt/buildbot/buildmaster-v3.11.8:sha-f2c82f2
    
    Fixes: 93918cc2e225 ("ci: add support for testing PR containers")
    Signed-off-by: Petr Štetiar <ynezz at true.cz>
---
 .github/workflows/build-push.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.github/workflows/build-push.yml b/.github/workflows/build-push.yml
index c9f07c6..774f7a5 100644
--- a/.github/workflows/build-push.yml
+++ b/.github/workflows/build-push.yml
@@ -148,8 +148,8 @@ jobs:
           tags: |
             type=raw,value=pr-${{ inputs.pr_number }},enable=${{ github.event_name == 'workflow_dispatch' }}
             type=ref,event=branch,enable=${{ github.event_name != 'workflow_dispatch' }}
+            type=ref,event=tag,enable=${{ github.event_name != 'workflow_dispatch' }}
             type=sha,prefix=sha-,enable=${{ github.event_name != 'workflow_dispatch' }}
-            type=semver,pattern={{version}}
 
       - name: Login to GitHub Container Registry
         uses: docker/login-action at v3