Support out of band dumping of unrooted slots in AccountsDb (backport #17269)

[mergify]

This is an automatic backport of pull request #17269 done by Mergify.
Cherry-pick of bbcdf07 has failed:

On branch mergify/bp/v1.7/pr-17269
Your branch is up to date with 'origin/v1.7'.

You are currently cherry-picking commit bbcdf073b.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Changes to be committed:
	modified:   core/src/repair_service.rs
	modified:   runtime/src/bank.rs

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   runtime/src/accounts_db.rs

To fix up this pull request, you can check it out locally. See documentation: https://help.github.com/articles/checking-out-pull-requests-locally/

---

Mergify commands and options

More conditions and actions can be found in the documentation.

You can also trigger Mergify actions by commenting on this pull request:

• @Mergifyio refresh will re-evaluate the rules
• @Mergifyio rebase will rebase this PR on its base branch
• @Mergifyio update will merge the base branch into this PR
• @Mergifyio backport <destination> will backport this PR on <destination> branch

Additionally, on Mergify dashboard you can:

• look at your merge queues
• generate the Mergify configuration with the config editor.

Finally, you can contact us on https://mergify.io/

[mergify]

automerge label removed due to a CI failure

[codecov]

Codecov Report

Merging #17777 (e47ab55) into v1.7 (e5ea16f) will increase coverage by 0.0%.
The diff coverage is 100.0%.

@@           Coverage Diff            @@
##             v1.7   #17777    +/-   ##
========================================
  Coverage    82.6%    82.6%            
========================================
  Files         432      432            
  Lines      120069   120172   +103     
========================================
+ Hits        99243    99352   +109     
+ Misses      20826    20820     -6