Cleanup backendmappings in history UI page

[raj-manvar]

Description

Currently the history.tsx which is for rendering the Query history page has backendMapping defined at https://github.com/trinodb/trino-gateway/blob/main/webapp/src/components/history.tsx#L18

It stores mapping between:
backend name -> backend proxy URL
backend proxy URL -> backend name
backend external Url -> backend name.

From usage, only the ProxyUrl -> backend Name mapping is used while displaying the backend name in the list of query history, rest mapping can be cleaned up.

Additional context and related issues

Release notes

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[andythsu]

For UI change, could you include a picture of before and after so it's clear on what the changes are?

[raj-manvar]

Yes Thanks, I can include this. Though, for this change we dont expect any UI changes, it's mostly just code cleanup. I'll add the UI screenshot after running the branch locally

[RoeyoOgen]

@raj-manvar any update?

[raj-manvar]

[raj-manvar]

[raj-manvar]

[raj-manvar]

[raj-manvar]

Sorry @RoeyoOgen for the delay. Added screenshot and also rebased with latest main branch

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[andythsu]

Do we still use backendMapping anywhere if you change it to b.name? Or we can completely remove it

[raj-manvar]

we still use it at

trino-gateway/webapp/src/components/history.tsx

Line 154 in 487137c

<Column title="Name" dataIndex="backendUrl" key="backendUrlName" render={(text: string) => <Text>{backendMapping[text]}</Text>} />