[buildbot] ci: avoid branch tags on workflow_dispatch

[LEDE Commits]

ynezz pushed a commit to buildbot.git, branch main:
https://git.openwrt.org/9470e52e6c181f223cd263bd3581d294ab4b2c35

commit 9470e52e6c181f223cd263bd3581d294ab4b2c35
Author: Petr Štetiar <ynezz at true.cz>
AuthorDate: Sun Jan 11 21:51:36 2026 +0100

    ci: avoid branch tags on workflow_dispatch
    
    Currently workflow_dispatch pushes branch tags, so lets fix it by
    disabling branch tagging for dispatch runs.
    
    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 ee9ec49..63f666a 100644
--- a/.github/workflows/build-push.yml
+++ b/.github/workflows/build-push.yml
@@ -146,7 +146,7 @@ jobs:
           images: ghcr.io/${{ github.repository }}/build${{ matrix.container_flavor }}-v${{ env.BUILDBOT_VERSION }}
           tags: |
             type=raw,value=pr-${{ inputs.pr_number }},enable=${{ github.event_name == 'workflow_dispatch' }}
-            type=ref,event=branch
+            type=ref,event=branch,enable=${{ github.event_name != 'workflow_dispatch' }}
             type=sha,prefix=sha-,enable=${{ github.event_name != 'workflow_dispatch' }}
             type=semver,pattern={{version}}