FileRepository: Remove unnecessary setConfig call

The constructor of GC sets exactly the same config. Remove this
set to make clearer from where the config is coming.

Change-Id: Idb71c7827f180923092ef5392545df81960ee93a
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/FileRepository.java b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/FileRepository.java
index b5d29a3..230dc6f 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/FileRepository.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/FileRepository.java
@@ -60,7 +60,6 @@
 import org.eclipse.jgit.revwalk.RevWalk;
 import org.eclipse.jgit.storage.file.FileBasedConfig;
 import org.eclipse.jgit.storage.file.FileRepositoryBuilder;
-import org.eclipse.jgit.storage.pack.PackConfig;
 import org.eclipse.jgit.transport.ReceiveCommand;
 import org.eclipse.jgit.util.FileUtils;
 import org.eclipse.jgit.util.IO;
@@ -595,7 +594,6 @@
 	@Override
 	public void autoGC(ProgressMonitor monitor) {
 		GC gc = new GC(this);
-		gc.setPackConfig(new PackConfig(this));
 		gc.setProgressMonitor(monitor);
 		gc.setAuto(true);
 		gc.setBackground(shouldAutoDetach());