deps: update dependency com.github.ben-manes.caffeine:caffeine to v2.9.1 (#165)

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This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [com.github.ben-manes.caffeine:caffeine](https://togithub.com/ben-manes/caffeine) | `2.9.0` -> `2.9.1` | [![age](https://badges.renovateapi.com/packages/maven/com.github.ben-manes.caffeine:caffeine/2.9.1/age-slim)](https://docs.renovatebot.com/merge-confidence/) | [![adoption](https://badges.renovateapi.com/packages/maven/com.github.ben-manes.caffeine:caffeine/2.9.1/adoption-slim)](https://docs.renovatebot.com/merge-confidence/) | [![passing](https://badges.renovateapi.com/packages/maven/com.github.ben-manes.caffeine:caffeine/2.9.1/compatibility-slim/2.9.0)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://badges.renovateapi.com/packages/maven/com.github.ben-manes.caffeine:caffeine/2.9.1/confidence-slim/2.9.0)](https://docs.renovatebot.com/merge-confidence/) |

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### Release Notes

<details>
<summary>ben-manes/caffeine</summary>

### [`v2.9.1`](https://togithub.com/ben-manes/caffeine/releases/v2.9.1)

[Compare Source](https://togithub.com/ben-manes/caffeine/compare/v2.9.0...v2.9.1)

Cache

-   Added cancellation of the next scheduled expiration cleanup when the cache becomes empty ([#&#8203;542](https://togithub.com/ben-manes/caffeine/issues/542))
-   Improved how variable expiration reorganizes the timer events ([#&#8203;541](https://togithub.com/ben-manes/caffeine/issues/541))
-   Added putIfAbsent optimistic fastpath ([#&#8203;506](https://togithub.com/ben-manes/caffeine/issues/506))

</details>

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---

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Author: renovate-bot

pom.xml

@@ -105,7 +105,7 @@
     <dependency>
       <groupId>com.github.ben-manes.caffeine</groupId>
       <artifactId>caffeine</artifactId>
-      <version>2.9.0</version>
+      <version>2.9.1</version>
     </dependency>
     <dependency>
       <groupId>org.scala-lang</groupId>