[Az.RecoveryServices.Backup] Register with -Force

[hiaga]

Description

Fixing the issue with the -Force parameter, which was asking from confirmation even after -Force and -Confirm were given

Checklist

• [x] I have read the Submitting Changes section of CONTRIBUTING.md
• [x] The title of the PR is clear and informative
• [x] The appropriate ChangeLog.md file(s) has been updated:
  • For any service, the ChangeLog.md file can be found at src/{{SERVICE}}/{{SERVICE}}/ChangeLog.md
  • A snippet outlining the change(s) made in the PR should be written under the ## Upcoming Release header -- no new version header should be added
• [x] The PR does not introduce breaking changes
• [ ] If applicable, the changes made in the PR have proper test coverage
• [ ] For public API changes to cmdlets:
  • [ ] a cmdlet design review was approved for the changes in this repository (Microsoft internal only)
    • {Please put the link here}
  • [x] the markdown help files have been regenerated using the commands listed here

[isra-fel]

Hi @hiaga I've marked this PR as draft for bookkeeping reason. Please click the "Ready for review" button when you've done working on it. Thanks.

[hiaga]

Not needed to be merged