Add ZombieVillager conversion without entity event (#8111)

The ZombieVillager#setConversionTime API method internally calls
startConversion which always broadcasts the entity event responsible for
playing the respective sound at the beginning of a conversion.

This is not always wanted by developers when modifying already
converting zombies in particular.

This commit expands the ZombieVillager interface with another overload
of the setConversionTime method that also takes a simple toggle flag
indicating whether or not the entity event should be published to the
world.

patches/api/Missing-Entity-Behavior-API.patch

@@ -701,3 +701,30 @@ index 0000000000000000000000000000000000000000..00000000000000000000000000000000
 +    boolean isInterested();
 +    // Paper end
  }
+diff --git a/src/main/java/org/bukkit/entity/ZombieVillager.java b/src/main/java/org/bukkit/entity/ZombieVillager.java
+index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
+--- a/src/main/java/org/bukkit/entity/ZombieVillager.java
++++ b/src/main/java/org/bukkit/entity/ZombieVillager.java
+@@ -0,0 +0,0 @@ public interface ZombieVillager extends Zombie {
+      * @param conversionPlayer the player
+      */
+     void setConversionPlayer(@Nullable OfflinePlayer conversionPlayer);
++
++    // Paper start - missing entity behaviour api - converting without entity event
++    /**
++     * Sets the amount of ticks until this entity will be converted to a
++     * Villager as a result of being cured.
++     * <p>
++     * When this reaches 0, the entity will be converted. A value of less than 0
++     * will stop the current conversion process without converting the current
++     * entity.
++     *
++     * @param time new conversion time
++     * @param broadcastEntityEvent whether this conversion time mutation should broadcast the
++     *                             org.bukkit.{@link org.bukkit.EntityEffect#ZOMBIE_TRANSFORM} entity event to the
++     *                             world. If false, no entity event is published, preventing for example the
++     *                             org.bukkit.{@link org.bukkit.Sound#ENTITY_ZOMBIE_VILLAGER_CURE} from playing.
++     */
++    void setConversionTime(int time, boolean broadcastEntityEvent);
++    // Paper stop - missing entity behaviour api - converting without entity event
+ }