chore(deps): bump com.openai:openai-java in /backend

Bumps [com.openai:openai-java](https://github.com/openai/openai-java) from 4.16.1 to 4.45.0.
- [Release notes](https://github.com/openai/openai-java/releases)
- [Changelog](https://github.com/openai/openai-java/blob/main/CHANGELOG.md)
- [Commits](openai/openai-java@v4.16.1...v4.45.0)

---
updated-dependencies:
- dependency-name: com.openai:openai-java
  dependency-version: 4.45.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

backend/pom.xml

@@ -237,7 +237,7 @@
         <dependency>
             <groupId>com.openai</groupId>
             <artifactId>openai-java</artifactId>
-            <version>4.16.1</version>
+            <version>4.45.0</version>
         </dependency>
 
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