release-25.1: kvserver: alias range_id in flow control integration tests

[blathers-crl]

Backport 7/7 commits from #138085 on behalf of @kvoli.

/cc @cockroachdb/release

---

Earlier commits are mechanical, reformatting and deduplicating SQL queries
used by the flow control integration tests.

---

Previously, the range_id of scratch ranges used in various
TestFlowControl.* tests would be printed into the testdata file. This
made it tedious to introduce new system tables, which in turn may create
new ranges and necessitate regenerating the
test_flow_control_integration testdata files to pick up the higher
default scratch range id.

Alias the range id to letters in a,b,...,z so that regardless of the
underlying scratch range id changing, the aliased scratch range id
remains unchanged. For example:

An old example:

SELECT
  range_id, count(*) AS streams
FROM
  crdb_internal.kv_flow_control_handles
GROUP BY
  (range_id)
ORDER BY
  streams DESC;

  range_id | stream_count
-----------+---------------
  75       | 3
  76       | 3

Now looks like:

SELECT
  chr(96 + DENSE_RANK() OVER (ORDER BY range_id)) as range_id,
  count(*) AS streams
FROM
  crdb_internal.kv_flow_control_handles
GROUP BY
  range_id
ORDER BY
  range_id;

  range_id | stream_count
-----------+---------------
  a        | 3
  b        | 3

Resolves: #137727
Release note: None

---

Release justification: Test only.

[blathers-crl]

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[blathers-crl]

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[cockroach-teamcity]

This change is 

[kvoli]

Failure on TestFlowControlV1ToV2Transition. Going to see if this reproduces locally.

[kvoli]

Failure on TestFlowControlV1ToV2Transition. Going to see if this reproduces locally.

It does, in around 5 minutes of --stress --race with:

dev test pkg/kv/kvserver -v --vmodule='replica_raft=1,kvflowcontroller=2,replica_proposal_buf=1,raft_transport=2,kvflowdispatch=1,kvadmission=1,kvflowhandle=1,work_queue=1,replica_flow_control=1,tracker=1,client_raft_helpers_test=1,raft=1,admission=1,replica_flow_control=1,work_queue=1,replica_raft=1,replica_proposal_buf=1,raft_transport=2,kvadmission=1,work_queue=1,replica_flow_control=1,client_raft_helpers_test=1,range_controller=3,token_counter=2,token_tracker=2,processor=2,kvflowhandle=1' -f TestFlowControlV1ToV2Transition --stress --race --cpus=16