deps: update golang docker tag to v1.26.2 (#4330)

Author: renovate-bot

samples/sidecar-proxy/Dockerfile

@@ -12,7 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-FROM golang:1.26.1 as builder
+FROM golang:1.26.2 as builder
 WORKDIR /app
 RUN go mod init example-app
 RUN go get github.com/jackc/pgx/v4