chore(deps): update dependency get_it to v8 (#443)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [get_it](https://redirect.github.com/fluttercommunity/get_it) |
dependencies | major | `^7.6.9` -> `^8.0.0` |

---

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> Some dependencies could not be looked up. Check the Dependency
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---

### Release Notes

<details>
<summary>fluttercommunity/get_it (get_it)</summary>

###
[`v8.0.0`](https://redirect.github.com/fluttercommunity/get_it/blob/HEAD/CHANGELOG.md#800-official-new-release-with-all-the-changes)

#### \[8.0.0] official new release with all the changes

</details>

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packages/ubuntu_service/pubspec.yaml

@@ -9,7 +9,7 @@ environment:
   sdk: '>=3.0.0 <4.0.0'
 
 dependencies:
-  get_it: ^7.6.9
+  get_it: ^8.0.0
   meta: ^1.15.0
 
 dev_dependencies: