chore: fix publish_docker.sh (#14851)

Started failing a few days ago (https://github.com/microsoft/playwright/runs/6871909784?check_suite_focus=true)
with:

```
./utils/docker/publish_docker.sh: line 82: syntax error near unexpected
token `else'
```

utils/docker/publish_docker.sh

@@ -78,7 +78,6 @@ publish_docker_images_with_arch_suffix() {
     TAGS=("${FOCAL_TAGS[@]}")
   elif [[ "$FLAVOR" == "jammy" ]]; then
     TAGS=("${JAMMY_TAGS[@]}")
-  else
   else
     echo "ERROR: unknown flavor - $FLAVOR. Must be either 'bionic' or 'focal'"
     exit 1