deps: update actions/setup-java action to v2 (#155)

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This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [actions/setup-java](https://togithub.com/actions/setup-java) | action | major | `v1` -> `v2` |

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### Release Notes

<details>
<summary>actions/setup-java</summary>

### [`v2`](https://togithub.com/actions/setup-java/compare/v1...v2)

[Compare Source](https://togithub.com/actions/setup-java/compare/v1...v2)

</details>

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Author: renovate-bot