fix(deps): update dependency com.google.api:api-common to v2.2.1 (#1699)

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

This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [com.google.api:api-common](https://github.com/googleapis/api-common-java) | `2.1.5` -> `2.2.1` | [![age](https://badges.renovateapi.com/packages/maven/com.google.api:api-common/2.2.1/age-slim)](https://docs.renovatebot.com/merge-confidence/) | [![adoption](https://badges.renovateapi.com/packages/maven/com.google.api:api-common/2.2.1/adoption-slim)](https://docs.renovatebot.com/merge-confidence/) | [![passing](https://badges.renovateapi.com/packages/maven/com.google.api:api-common/2.2.1/compatibility-slim/2.1.5)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://badges.renovateapi.com/packages/maven/com.google.api:api-common/2.2.1/confidence-slim/2.1.5)](https://docs.renovatebot.com/merge-confidence/) |

---

### Configuration

📅 **Schedule**: Branch creation - At any time (no schedule defined), Automerge - At any time (no schedule defined).

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

♻ **Rebasing**: Renovate will not automatically rebase this PR, because other commits have been found.

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

---

 - [ ] <!-- rebase-check -->If you want to rebase/retry this PR, click this checkbox. ⚠ **Warning**: custom changes will be lost.

---

This PR has been generated by [Mend Renovate](https://www.mend.io/free-developer-tools/renovate/). View repository job log [here](https://app.renovatebot.com/dashboard#github/googleapis/gax-java).

gax-java/pom.xml

@@ -56,7 +56,7 @@
       <dependency>
         <groupId>com.google.api</groupId>
         <artifactId>api-common</artifactId>
-        <version>2.1.5</version>
+        <version>2.2.1</version>
       </dependency>
       <dependency>
         <groupId>com.google.auth</groupId>