chore(deps): update dependency io.camunda:camunda-process-test-spring to v8.8.12

Author: renovate[bot]

pom.xml

@@ -15,7 +15,7 @@
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
     <version.connectors>8.8.7</version.connectors>
-    <version.camunda>8.8.9</version.camunda>
+    <version.camunda>8.8.12</version.camunda>
     <version.assertj>3.27.4</version.assertj>
     <version.junit-jupiter>6.0.2</version.junit-jupiter>
     <version.awaitility>4.2.0</version.awaitility>