Bump software.amazon.awssdk:bom in /labs/unicorn-stock-broker

Bumps software.amazon.awssdk:bom from 2.25.45 to 2.26.15.

---
updated-dependencies:
- dependency-name: software.amazon.awssdk:bom
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

labs/unicorn-stock-broker/pom.xml

@@ -17,7 +17,7 @@
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
         <spring-cloud.version>2023.0.2</spring-cloud.version>
-        <aws-sdk.version>2.25.45</aws-sdk.version>
+        <aws-sdk.version>2.26.15</aws-sdk.version>
     </properties>
 
     <dependencies>