Refactor util for setting BukkitService mock behavior

- Move helper methods for setting BukkitService mock behavior into their own class
- Change methods to use Mockito's answer instead of verification + argument capture -> calling the methods now belongs to the test setup (given clause) and allows the behavior to take effect more than once

src/test/java/fr/xephi/authme/TestHelper.java

@@ -1,10 +1,8 @@
 package fr.xephi.authme;
 
 import ch.jalu.configme.properties.Property;
-import fr.xephi.authme.service.BukkitService;
 import fr.xephi.authme.settings.Settings;
 import org.bukkit.entity.Player;
-import org.mockito.ArgumentCaptor;
 import org.mockito.Mockito;
 
 import java.io.File;
@@ -21,11 +19,8 @@ import java.nio.file.Paths;
 import java.util.logging.Logger;
 
 import static org.mockito.ArgumentMatchers.any;
-import static org.mockito.ArgumentMatchers.anyLong;
 import static org.mockito.BDDMockito.given;
-import static org.mockito.Mockito.doAnswer;
 import static org.mockito.Mockito.mock;
-import static org.mockito.Mockito.verify;
 
 /**
  * AuthMe test utilities.
@@ -78,76 +73,6 @@ public final class TestHelper {
         }
     }
 
-    /**
-     * Execute a {@link Runnable} passed to a mock's {@link BukkitService#runTaskAsynchronously} method.
-     * Note that calling this method expects that there be a runnable sent to the method and will fail
-     * otherwise.
-     *
-     * @param service The mock service
-     */
-    public static void runInnerRunnable(BukkitService service) {
-        ArgumentCaptor<Runnable> captor = ArgumentCaptor.forClass(Runnable.class);
-        verify(service).runTaskAsynchronously(captor.capture());
-        Runnable runnable = captor.getValue();
-        runnable.run();
-    }
-
-    /**
-     * Execute a {@link Runnable} passed to a mock's {@link BukkitService#runTaskOptionallyAsync} method.
-     * Note that calling this method expects that there be a runnable sent to the method and will fail
-     * otherwise.
-     *
-     * @param service The mock service
-     */
-    public static void runOptionallyAsyncTask(BukkitService service) {
-        ArgumentCaptor<Runnable> captor = ArgumentCaptor.forClass(Runnable.class);
-        verify(service).runTaskOptionallyAsync(captor.capture());
-        Runnable runnable = captor.getValue();
-        runnable.run();
-    }
-
-    /**
-     * Execute a {@link Runnable} passed to a mock's {@link BukkitService#scheduleSyncDelayedTask(Runnable)}
-     * method. Note that calling this method expects that there be a runnable sent to the method and will fail
-     * otherwise.
-     *
-     * @param service The mock service
-     */
-    public static void runSyncDelayedTask(BukkitService service) {
-        ArgumentCaptor<Runnable> captor = ArgumentCaptor.forClass(Runnable.class);
-        verify(service).scheduleSyncDelayedTask(captor.capture());
-        Runnable runnable = captor.getValue();
-        runnable.run();
-    }
-
-    /**
-     * Execute a {@link Runnable} passed to a mock's {@link BukkitService#scheduleSyncDelayedTask(Runnable, long)}
-     * method. Note that calling this method expects that there be a runnable sent to the method and will fail
-     * otherwise.
-     *
-     * @param service The mock service
-     */
-    public static void runSyncDelayedTaskWithDelay(BukkitService service) {
-        ArgumentCaptor<Runnable> captor = ArgumentCaptor.forClass(Runnable.class);
-        verify(service).scheduleSyncDelayedTask(captor.capture(), anyLong());
-        Runnable runnable = captor.getValue();
-        runnable.run();
-    }
-
-    /**
-     * Sets a BukkitService mock to run any Runnable it is passed to its method
-     * {@link BukkitService#scheduleSyncTaskFromOptionallyAsyncTask}.
-     *
-     * @param bukkitService the mock to set behavior on
-     */
-    public static void setBukkitServiceToRunOptionallyAsyncTasks(BukkitService bukkitService) {
-        doAnswer(invocation -> {
-            Runnable runnable = invocation.getArgument(0);
-            runnable.run();
-            return null;
-        }).when(bukkitService).scheduleSyncTaskFromOptionallyAsyncTask(any(Runnable.class));
-    }
-
     /**
      * Assign the necessary fields on ConsoleLogger with mocks.
      *