chore(deps): update dependency io.cloudevents:cloudevents-core to v4 (#284)

Co-authored-by: Jeremy Fehr <[email protected]>

Author: renovate-bot

invoker/conformance/pom.xml

@@ -38,7 +38,7 @@
     <dependency>
       <groupId>io.cloudevents</groupId>
       <artifactId>cloudevents-core</artifactId>
-      <version>3.0.0</version>
+      <version>4.0.1</version>
     </dependency>
     <dependency>
       <groupId>io.cloudevents</groupId>