TAN-2792: Turn on unnecessary lint rule

[EdwinKato]

Changelog

Technical

• This updates the ESLint configuration to enforce the @typescript-eslint/no-unnecessary-condition rule as an error. This rule helps identify conditions that are always truthy or falsy based on TypeScript's type analysis, ensuring that our code is more accurate and free of unnecessary checks. For now, most current violations have been commented out but we can phase them out as we edit these files

[notion-workspace[bot]]

Turn on no unnecessary condition or add exceptions and comments for them

[cl-dev-bot]

	Messages
:book:	Changelog provided 🎉
:book:	Notion issue: TAN-2792
:book:	Run the e2e tests
:book:	Check translation progress

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