chore(deps): update dependency google-cloud-asset to v2.2.0 (#117)

[![WhiteSource Renovate](https://app.renovatebot.com/images/banner.svg)](https://renovatebot.com)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| [google-cloud-asset](https://togithub.com/googleapis/python-asset) | minor | `==2.1.0` -> `==2.2.0` |

---

### Release Notes

<details>
<summary>googleapis/python-asset</summary>

### [`v2.2.0`](https://togithub.com/googleapis/python-asset/blob/master/CHANGELOG.md#&#8203;220-httpswwwgithubcomgoogleapispython-assetcomparev210v220-2020-11-19)

[Compare Source](https://togithub.com/googleapis/python-asset/compare/v2.1.0...v2.2.0)

##### Features

-   add AnalyzeIamPolicy and ExportIamPolicyAnalysis; support OSInventory; add common resource helper methods; expose client transport ([#&#8203;113](https://www.github.com/googleapis/python-asset/issues/113)) ([3bf4c0a](https://www.github.com/googleapis/python-asset/commit/3bf4c0ab20346e3a12af168e20139f2cc067540a))

##### Documentation

-   remove note on editable installs ([#&#8203;99](https://www.github.com/googleapis/python-asset/issues/99)) ([cf6072a](https://www.github.com/googleapis/python-asset/commit/cf6072a09b76dce78bd4c0c471c8c2d81186e0c6))

</details>

---

### Renovate configuration

:date: **Schedule**: At any time (no schedule defined).

:vertical_traffic_light: **Automerge**: Disabled by config. Please merge this manually once you are satisfied.

:recycle: **Rebasing**: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

:no_bell: **Ignore**: Close this PR and you won't be reminded about this update again.

---

 - [ ] <!-- rebase-check -->If you want to rebase/retry this PR, check this box

---

This PR has been generated by [WhiteSource Renovate](https://renovate.whitesourcesoftware.com). View repository job log [here](https://app.renovatebot.com/dashboard#github/googleapis/python-asset).

samples/snippets/requirements.txt

@@ -1,5 +1,5 @@
 google-cloud-storage==1.33.0
-google-cloud-asset==2.1.0
+google-cloud-asset==2.2.0
 google-cloud-resource-manager==0.30.2
 google-cloud-pubsub==1.7.0
 google-cloud-bigquery==2.4.0