JSON escape the change log entry

What does this MR do?

This MR relates to gitlab-org/gitlab#285443 (closed)

Some characters in a changelog message can cause the deployment to fail. This MR aims to escape such characters.

Example problematic changelog message:

- Improve ability to find the "login" button when running authenticated scans (!342)

This message would result in the

{"tag_name":"v1.33.1","description":" ##### Changes\n - Improve ability to find the "login" button when running authenticated scans (!342)"}

This MR updates that message to:

{"tag_name":"v1.33.1","description":" ##### Changes\n - Improve ability to find the \"login\" button when running authenticated scans (!342)"}

What are the relevant issue numbers?

Does this MR meet the acceptance criteria?

• Changelog entry added
• Documentation created/updated for GitLab EE, if necessary
• 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
  • Job definition example
  • Vendored CI Templates (also in CE)
• Conforms to the code review guidelines
• Conforms to the Go guidelines
• Security reports checked/validated by reviewer