[lint] Add "caughtErrors: 'all'" to linter config (#16591)

Why
---
ES2019 added "optional catch bindings" so that `e`/`error`/etc. don't need to be specified in catch clauses if the thrown value i

[lint] Add "caughtErrors: 'all'" to linter config (#16591)

Why
---
ES2019 added "optional catch bindings" so that `e`/`error`/etc. don't need to be specified in catch clauses if the thrown value isn't used. This changes our lint rules to warn if unnecessary error variables are declared. https://2ality.com/2017/08/optional-catch-binding.html.

In JS, as opposed to TS, we allow unused catch bindings if the variable names are prefixed with an underscore. This is so that JS targeting older JS interpreters can write `catch (_) {}` if needed. With TS we disallow unused catch bindings since tsc can compile code to its target JS version.

How
---
Added `caughtErrors: 'all'` to the no-unused-vars rule's configuration. As part of this change, I made the TypeScript linting rules apply only to .ts/.tsx/.ts.d files and updated the unit test snapshots.

Test Plan
---
Added unit tests to the linter. Ran linter over all modules in this repo with expotools.

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