deps: update dependency com.google.api:gax-bom to v2.22.0 (#1084)

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This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [com.google.api:gax-bom](https://togithub.com/googleapis/java-shared-config) ([source](https://togithub.com/googleapis/gax-java)) | `2.21.0` -> `2.22.0` | [![age](https://badges.renovateapi.com/packages/maven/com.google.api:gax-bom/2.22.0/age-slim)](https://docs.renovatebot.com/merge-confidence/) | [![adoption](https://badges.renovateapi.com/packages/maven/com.google.api:gax-bom/2.22.0/adoption-slim)](https://docs.renovatebot.com/merge-confidence/) | [![passing](https://badges.renovateapi.com/packages/maven/com.google.api:gax-bom/2.22.0/compatibility-slim/2.21.0)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://badges.renovateapi.com/packages/maven/com.google.api:gax-bom/2.22.0/confidence-slim/2.21.0)](https://docs.renovatebot.com/merge-confidence/) |

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pom.xml

@@ -151,7 +151,7 @@
     <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
     <github.global.server>github</github.global.server>
     <site.installationModule>google-cloud-core-parent</site.installationModule>
-    <gax.version>2.21.0</gax.version>
+    <gax.version>2.22.0</gax.version>
     <google.api-common.version>2.5.0</google.api-common.version>
     <google.common-protos.version>2.13.0</google.common-protos.version>
     <google.iam.version>1.8.0</google.iam.version>