sql,backupccl: add more tests for user ID migrations

[andyyang890]

sql: add mixed version test for system.privileges user ID migration

This patch adds a mixed version logic test that ensures granting of
system privileges continues to work properly in a cluster that has
both 22.2 and 23.1 nodes. The relevant version gate being tested here
is V23_1SystemPrivilegesTableHasUserIDColumn.

Release note: None

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sql: add mixed version test for system.database_role_settings user IDs

This patch adds a mixed version logic test that ensures setting default
session variables continues to work properly in a cluster that has
both 22.2 and 23.1 nodes. The relevant version gate being tested here
is V23_1DatabaseRoleSettingsHasRoleIDColumn.

Release note: None

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backupccl: update TestRestoreOldVersions subtest for system.privileges

This patch updates the TestRestoreOldVersions subtest for the
system.privileges table to also test that a row for the public
role is correctly restored.

Release note: None

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Part of #87079
Part of #92342

[cockroach-teamcity]

This change is 

[rafiss]

lgtm!

[andyyang890]

TFTR!

bors r=rafiss

[craig]

Build failed (retrying...):

• Bazel Essential CI (Cockroach)

[craig]

Build failed (retrying...):

• Bazel Essential CI (Cockroach)

[craig]

Build failed (retrying...):

• Bazel Essential CI (Cockroach)

[craig]

Build failed (retrying...):

• Bazel Essential CI (Cockroach)

[craig]

Build failed:

• Bazel Essential CI (Cockroach)

[andyyang890]

bors r=rafiss

[andyyang890]

bors ping

[craig]

pong

[andyyang890]

seems like bors is stuck

bors r-

[craig]

Canceled.

[andyyang890]

bors r=rafiss

[craig]

Build succeeded:

• Bazel Essential CI (Cockroach)

[blathers-crl]

Encountered an error creating backports. Some common things that can go wrong:

1. The backport branch might have already existed.
2. There was a merge conflict.
3. The backport branch contained merge commits.

You might need to create your backport manually using the backport tool.

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error creating merge commit from 7bf12b6 to blathers/backport-release-23.1-99533: POST https://api.github.com/repos/cockroachdb/cockroach/merges: 409 Merge conflict []

you may need to manually resolve merge conflicts with the backport tool.

Backport to branch 23.1.x failed. See errors above.

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