Bump to 4.0.0-SNAPSHOT for gremlin-mcp CTR

Author: spmallette

gremlin-mcp/pom.xml

@@ -22,7 +22,7 @@ limitations under the License.
     <parent>
         <groupId>org.apache.tinkerpop</groupId>
         <artifactId>tinkerpop</artifactId>
-        <version>3.8.0-SNAPSHOT</version>
+        <version>4.0.0-SNAPSHOT</version>
     </parent>
 
     <artifactId>gremlin-mcp</artifactId>