Bump org.a2aproject.sdk:a2a-java-sdk-client (#1623)

Bumps org.a2aproject.sdk:a2a-java-sdk-client from 1.1.0.Final to 1.2.0.Final.

---
updated-dependencies:
- dependency-name: org.a2aproject.sdk:a2a-java-sdk-client
  dependency-version: 1.2.0.Final
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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Author: dependabot[bot]

impl/pom.xml

@@ -17,7 +17,7 @@
         <version.com.cronutils>9.2.1</version.com.cronutils>
         <version.docker.java>3.7.1</version.docker.java>
         <version.org.graalvm.polyglot>25.2.4</version.org.graalvm.polyglot>
-        <version.org.a2aproject.sdk>1.1.0.Final</version.org.a2aproject.sdk>
+        <version.org.a2aproject.sdk>1.2.0.Final</version.org.a2aproject.sdk>
         <version.com.google.code.gson>2.14.0</version.com.google.code.gson>
     </properties>
     <dependencyManagement>