refactor: rename roomNumber method to number in RoomBuilder

Author: otaviojava

src/main/java/org/soujava/demos/mongodb/document/RoomBuilder.java

@@ -14,7 +14,7 @@ public RoomBuilder id(String id) {
         return this;
     }
 
-    public RoomBuilder roomNumber(int roomNumber) {
+    public RoomBuilder number(int roomNumber) {
         this.roomNumber = roomNumber;
         return this;
     }