Improvements for update-wb.

- Better detection of the current image in use, will update if the image
  was already downloaded.
- Kill all tmux instances, otherwise it keeps running and but
  malfunctions.

Documents/bin/update-wb

@@ -7,7 +7,7 @@ CONTAINER='workbench'
 is_latest() {
     podman image exists "$IMAGE" || return 1
     toolbox run --container "$CONTAINER" true 2>/dev/null || return 1
-    current="$(podman image inspect "$IMAGE" --format '{{.Digest}}')"
+    current="$(podman container inspect "$CONTAINER" --format '{{ .Image }}')"
     podman image pull --quiet "$IMAGE" > /dev/null
     new="$(podman image inspect "$IMAGE" --format '{{.Digest}}')"
     [ "$new" = "$current" ] || return 1
@@ -16,6 +16,7 @@ is_latest() {
 update() {
     toolbox rm --force "$CONTAINER" 2>/dev/null || true
     yes | podman image prune --filter 'label=com.github.containers.toolbox=true'
+    killall tmux || true
     toolbox create --image "$IMAGE"
 }