Bump org.springframework:spring-core (#255)

Bumps [org.springframework:spring-core](https://github.com/spring-projects/spring-framework) from 5.2.24.RELEASE to 6.0.15.
- [Release notes](https://github.com/spring-projects/spring-framework/releases)
- [Commits](https://github.com/spring-projects/spring-framework/compare/v5.2.24.RELEASE...v6.0.15)

---
updated-dependencies:
- dependency-name: org.springframework:spring-core
  dependency-type: direct:development
...

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function-based-stream-app-samples/image-thumbnail-samples/image-thumbnail-processor/pom.xml

@@ -33,7 +33,7 @@
 		<dependency>
 			<groupId>org.springframework</groupId>
 			<artifactId>spring-core</artifactId>
-			<version>5.2.24.RELEASE</version>
+			<version>6.0.15</version>
 			<scope>test</scope>
 		</dependency>
 	</dependencies>