Remove place-holder

Author: adamretter

.github/workflows/ci.yml

@@ -98,9 +98,11 @@
 
     <pluginManagement>
       <plugins>
-        <groupId>org.codehaus.mojo</groupId>
-        <artifactId>exec-maven-plugin</artifactId>
-        <version>3.0.0</version>
+        <plugin>
+          <groupId>org.codehaus.mojo</groupId>
+          <artifactId>exec-maven-plugin</artifactId>
+          <version>3.0.0</version>
+        </plugin>
       </plugins>
     </pluginManagement>