Add comment to ensure driver/server dependencies are in synch (#867)

Author: gjmwoods

pom.xml

@@ -63,11 +63,17 @@
         <version>1.0.3</version>
       </dependency>
       <dependency>
+        <!-- Please note that when updating this dependency -->
+        <!-- (i.e. due to a security vulnerability or bug) that the -->
+        <!-- corresponding server dependency also needs updating.-->
         <groupId>io.netty</groupId>
         <artifactId>netty-handler</artifactId>
         <version>4.1.59.Final</version>
       </dependency>
       <dependency>
+        <!-- Please note that when updating this dependency -->
+        <!-- (i.e. due to a security vulnerability or bug) that the -->
+        <!-- corresponding server dependency also needs updating.-->
         <groupId>io.projectreactor</groupId>
         <artifactId>reactor-bom</artifactId>
         <version>Dysprosium-SR17</version>