Fix prettier-yaml restyler error. (#27277)

See
https://github.com/restyled-io/restyler/issues/208#issuecomment-1593198441 item
3: we are pinning a specific version of the prettier image, which means we have
to use a command syntax that works with that version.
diff --git a/.restyled.yaml b/.restyled.yaml
index 75613cb..a57f9ce 100644
--- a/.restyled.yaml
+++ b/.restyled.yaml
@@ -190,6 +190,9 @@
     - name: prettier-yaml
       image: restyled/restyler-prettier:v1.19.1-2
       enabled: true
+      command:
+          - prettier
+          - "--write"
       include:
           - "**/*.yml"
           - "**/*.yaml"