Stop explicitly blocking Vanilla Method Profiler

At the time this was re-added, there was concern around how the JIT
would handle the system property that enabled it.

This shouldn't be a problem, and as such we no longer need to block
access to it.

The Vanilla Method Profiler will not provide much to most users however
there is no harm in providing it as an option. For most users, the
recommended and supported method for determining performance issues with
Paper will continue to be Timings.

Spigot-Server-Patches/ExperienceOrbMergeEvent.patch

@@ -8,7 +8,7 @@ Plugins can cancel this if they want to ensure experience orbs do not lose impor
 metadata such as spawn reason, or conditionally move data from source to target.
 
 diff --git a/src/main/java/net/minecraft/server/World.java b/src/main/java/net/minecraft/server/World.java
-index e4502551b..9f5388ed9 100644
+index e4502551..9f5388ed 100644
 --- a/src/main/java/net/minecraft/server/World.java
 +++ b/src/main/java/net/minecraft/server/World.java
 @@ -0,0 +0,0 @@ public abstract class World implements IBlockAccess {