Updating elixir docker image, sobelow version

What does this MR do?

There have been new releases of both elixir as well as sobelow. This MR brings them into the analyzer for use as part of the product.

What are the relevant issue numbers?

gitlab-org/gitlab#214083 (closed)

Does this MR meet the acceptance criteria?

• Changelog entry added
• Documentation created/updated for GitLab EE https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/10527
• Documentation created/updated for this project, if necessary
• Documentation reviewed by technical writer or follow-up review issue created
• Tests added for this feature/bug
• Job definition updated, if necessary
  • Auto-DevOps template
  • Job definition example
  • CI Templates
• Conforms to the code review guidelines
• Conforms to the Go guidelines
• Security reports checked/validated by reviewer