Update docker/setup-buildx-action action to v4

.gitea/workflows/docker-build.yml

@@ -7,7 +7,7 @@ jobs:
     runs-on: ubuntu
     steps:
       - name: Set up Docker Buildx
-        uses: docker/setup-buildx-action@v3
+        uses: docker/setup-buildx-action@v4
       - name: Check out repository code
         uses: actions/checkout@v6
       - name: Login to Docker Registry

build/Dockerfile

@@ -1,5 +1,5 @@
 ARG BUILDPLATFORM
-FROM --platform=$BUILDPLATFORM golang:1.27-alpine AS builder
+FROM --platform=$BUILDPLATFORM golang:1.26-alpine AS builder
 
 # Set working directory
 WORKDIR /app