Bump schemahero/schemahero from 0.12.2 to 0.12.4 in /migrations/deploy

Bumps schemahero/schemahero from 0.12.2 to 0.12.4.

---
updated-dependencies:
- dependency-name: schemahero/schemahero
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

migrations/deploy/Dockerfile

@@ -1,4 +1,4 @@
-FROM schemahero/schemahero:0.12.2
+FROM schemahero/schemahero:0.12.4
 
 USER root
 RUN apt-get update && apt-get install -y --only-upgrade --no-install-recommends \