Add some basic access checks to the example database command

Author: I-Al-Istannen

application/src/main/java/org/togetherjava/tjbot/DatabaseListener.java

@@ -1,5 +1,6 @@
 package org.togetherjava.tjbot;
 
+import net.dv8tion.jda.api.Permission;
 import net.dv8tion.jda.api.entities.ChannelType;
 import net.dv8tion.jda.api.events.message.MessageReceivedEvent;
 import net.dv8tion.jda.api.hooks.ListenerAdapter;
@@ -53,6 +54,15 @@ public void onMessageReceived(MessageReceivedEvent event) {
         if (!event.isFromType(ChannelType.TEXT)) {
             return;
         }
+        if (event.isWebhookMessage()) {
+            return;
+        }
+        if (event.isFromType(ChannelType.PRIVATE)) {
+            return;
+        }
+        if (!event.getMember().hasPermission(Permission.MESSAGE_MANAGE)) {
+            return;
+        }
 
         String message = event.getMessage().getContentDisplay();
         if (message.startsWith("!dbput")) {