Bump snyk-sbt-plugin and snyk

Removes [snyk-sbt-plugin](https://github.com/snyk/snyk-sbt-plugin). It's no longer used after updating ancestor dependency [snyk](https://github.com/snyk/snyk). These dependencies need to be updated together.


Removes `snyk-sbt-plugin`

Updates `snyk` from 1.509.0 to 1.1236.0
- [Release notes](https://github.com/snyk/snyk/releases)
- [Commits](snyk/cli@v1.509.0...v1.1236.0)

---
updated-dependencies:
- dependency-name: snyk-sbt-plugin
  dependency-type: indirect
- dependency-name: snyk
  dependency-type: direct:production
...

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