improvement: S3C 1139 implement batch delete for sproxyd client

[dora-korpar]

Adds the changes for 8.1 that were implemented in scality/cloudserver#1869

[bert-e]

Hello dora-korpar,

My role is to assist you with the merge of this
pull request. Please type @bert-e help to get information
on this process, or consult the user documentation.

Status report is not available.

[bert-e]

Waiting for approval

The following approvals are needed before I can proceed with the merge:

• the author

• 2 peers

Peer approvals must include at least 1 approval from the following list:

• @rachedbenmustapha

• @rahulreddy

• @bennettbuchanan

[dora-korpar]

@bert-e approve

[bert-e]

In the queue

The changeset has received all authorizations and has been added to the
relevant queue(s). The queue(s) will be merged in the target development
branch(es) as soon as builds have passed.

The changeset will be merged in:

• ✔️ development/8.1

The following branches will NOT be impacted:

• development/6.4
• development/7.4
• development/7.5
• development/8.0
• stabilization/7.4.4

There is no action required on your side. You will be notified here once
the changeset has been merged. In the unlikely event that the changeset
fails permanently on the queue, a member of the admin team will
contact you to help resolve the matter.

IMPORTANT

Please do not attempt to modify this pull request.

• Any commit you add on the source branch will trigger a new cycle after the
  current queue is merged.
• Any commit you add on one of the integration branches will be lost.

If you need this pull request to be removed from the queue, please contact a
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The following options are set: approve

[bert-e]

I have successfully merged the changeset of this pull request
into targetted development branches:

• ✔️ development/8.1

The following branches have NOT changed:

• development/6.4
• development/7.4
• development/7.5
• development/8.0
• stabilization/7.4.4

Please check the status of the associated issue S3C-1139.

Goodbye dora-korpar.