release-22.2: ui: insights transaction details support multiple blocking transactions

[blathers-crl]

Backport 1/1 commits from #88454 on behalf of @j82w.

/cc @cockroachdb/release

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This adds support for multiple blocking transactions for a single waiting transaction. The cards were merged into the table, and the data was piped through to show multiple rows. The total contention time was also fixed to aggregate the contention time instead of just picking the latest.

before:
https://loom.com/share/0384ed937a344e2fb0105fefbc313acb

after:
https://www.loom.com/share/78e906f50a694cd59ac893ddb9c2239a

closes #88264

Release justification: Category 2: Bug fixes and
low-risk updates to new functionality

Release note: (ui change): Add support for multiple
blocking transaction on insights transaction
details page. Merged the cards into the table,
and fixed the total contention time.

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Release justification:

[blathers-crl]

Thanks for opening a backport.

Please check the backport criteria before merging:

• Patches should only be created for serious issues or test-only changes.
• Patches should not break backwards-compatibility.
• Patches should change as little code as possible.
• Patches should not change on-disk formats or node communication protocols.
• Patches should not add new functionality.
• Patches must not add, edit, or otherwise modify cluster versions; or add version gates.

If some of the basic criteria cannot be satisfied, ensure that the exceptional criteria are satisfied within.

• There is a high priority need for the functionality that cannot wait until the next release and is difficult to address in another way.
• The new functionality is additive-only and only runs for clusters which have specifically “opted in” to it (e.g. by a cluster setting).
• New code is protected by a conditional check that is trivial to verify and ensures that it only runs for opt-in clusters.
• The PM and TL on the team that owns the changed code have signed off that the change obeys the above rules.

Add a brief release justification to the body of your PR to justify this backport.

Some other things to consider:

• What did we do to ensure that a user that doesn’t know & care about this backport, has no idea that it happened?
• Will this work in a cluster of mixed patch versions? Did we test that?
• If a user upgrades a patch version, uses this feature, and then downgrades, what happens?

[cockroach-teamcity]

This change is 

[maryliag]

Reviewable status: complete! 1 of 0 LGTMs obtained (waiting on @ericharmeling and @kevin-v-ngo)