chore(angular): remove tslint (#28528)

Issue number: N/A

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## What is the current behavior?
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Ionic Framework migrated to using `eslint` for linting all of our
projects awhile ago. However we left around an unused tslint config file
in the Angular project by accident.

## What is the new behavior?
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this PR. -->

- Removes the unused tslint configuration file

## Does this introduce a breaking change?

- [ ] Yes
- [x] No

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and migration path for existing applications below. -->


## Other information

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screenshots of how the component looks before and after the change. -->