deps: update dependency org.apache.httpcomponents:httpcore to v4.4.16 (googleapis#1787)

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This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [org.apache.httpcomponents:httpcore](http://hc.apache.org/httpcomponents-core-ga) | `4.4.15` -> `4.4.16` | [![age](https://badges.renovateapi.com/packages/maven/org.apache.httpcomponents:httpcore/4.4.16/age-slim)](https://docs.renovatebot.com/merge-confidence/) | [![adoption](https://badges.renovateapi.com/packages/maven/org.apache.httpcomponents:httpcore/4.4.16/adoption-slim)](https://docs.renovatebot.com/merge-confidence/) | [![passing](https://badges.renovateapi.com/packages/maven/org.apache.httpcomponents:httpcore/4.4.16/compatibility-slim/4.4.15)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://badges.renovateapi.com/packages/maven/org.apache.httpcomponents:httpcore/4.4.16/confidence-slim/4.4.15)](https://docs.renovatebot.com/merge-confidence/) |

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Author: renovate-bot

pom.xml

@@ -570,7 +570,7 @@
     <project.guava.version>30.1.1-android</project.guava.version>
     <project.xpp3.version>1.1.4c</project.xpp3.version>
     <project.httpclient.version>4.5.13</project.httpclient.version>
-    <project.httpcore.version>4.4.15</project.httpcore.version>
+    <project.httpcore.version>4.4.16</project.httpcore.version>
     <project.opencensus.version>0.31.1</project.opencensus.version>
     <project.root-directory>..</project.root-directory>
     <deploy.autorelease>false</deploy.autorelease>