deps: update dependency com.google.flogger:flogger-system-backend to v0.8 (#1528)

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This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [com.google.flogger:flogger-system-backend](https://togithub.com/google/flogger) | `0.7.4` -> `0.8` | [![age](https://developer.mend.io/api/mc/badges/age/maven/com.google.flogger:flogger-system-backend/0.8?slim=true)](https://docs.renovatebot.com/merge-confidence/) | [![adoption](https://developer.mend.io/api/mc/badges/adoption/maven/com.google.flogger:flogger-system-backend/0.8?slim=true)](https://docs.renovatebot.com/merge-confidence/) | [![passing](https://developer.mend.io/api/mc/badges/compatibility/maven/com.google.flogger:flogger-system-backend/0.7.4/0.8?slim=true)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://developer.mend.io/api/mc/badges/confidence/maven/com.google.flogger:flogger-system-backend/0.7.4/0.8?slim=true)](https://docs.renovatebot.com/merge-confidence/) |

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Author: renovate-bot

google-cloud-pubsublite/pom.xml

@@ -110,7 +110,7 @@
     <dependency>
       <groupId>com.google.flogger</groupId>
       <artifactId>flogger-system-backend</artifactId>
-      <version>0.7.4</version>
+      <version>0.8</version>
       <scope>runtime</scope>
     </dependency>