Support setting a site name for Kafka consumers

[Kerkesni]

Code in backbeatConsumer already supports setting the client.rack consumer parameter from the config. So here i just allow passing that field in the config as we do in S3C

Issue: BB-521

[bert-e]

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 69.34%. Comparing base (a1e9895) to head (4b03c50).

Additional details and impacted files

Files with missing lines	Coverage Δ
lib/config.joi.js	100.00% <ø> (ø)

... and 1 file with indirect coverage changes

Components	Coverage Δ
Bucket Notification	66.66% <ø> (ø)
Core Library	74.02% <ø> (+0.01%)	⬆️
Ingestion	68.70% <ø> (ø)
Lifecycle	74.86% <ø> (ø)
Oplog Populator	82.95% <ø> (ø)
Replication	57.42% <ø> (ø)
Bucket Scanner	85.76% <ø> (ø)

@@               Coverage Diff                @@
##           development/8.6    #2547   +/-   ##
================================================
  Coverage            69.33%   69.34%           
================================================
  Files                  194      194           
  Lines                12791    12791           
================================================
+ Hits                  8869     8870    +1     
+ Misses                3912     3911    -1     
  Partials                10       10           

Flag	Coverage Δ
api:retry	9.66% <ø> (ø)
api:routes	9.56% <ø> (ø)
bucket-scanner	85.76% <ø> (ø)
ingestion	12.47% <ø> (ø)
lib	7.56% <ø> (+<0.01%)	⬆️
lifecycle	19.39% <ø> (ø)
notification	0.88% <ø> (ø)
replication	18.97% <ø> (ø)
unit	42.94% <ø> (ø)

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[bert-e]

Waiting for approval

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

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[Kerkesni]

/approve

[bert-e]

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• development/8.6

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[bert-e]

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

• ✔️ development/8.7

The following branches have NOT changed:

• development/7.10
• development/7.4
• development/7.70
• development/8.5
• development/8.6

Please check the status of the associated issue BB-521.

Goodbye kerkesni.