Revert "Changed upgrade backup to be placed in /tmp to avoid build-up #150"

This reverts commit c7219c6

Author: itzg

bedrock-entry.sh

@@ -85,7 +85,7 @@ if [ ! -f "bedrock_server-${VERSION}" ]; then
   # remove only binaries and some docs, to allow for an upgrade of those
   rm -rf bedrock_server *.so release-notes.txt bedrock_server_how_to.html valid_known_packs.json premium_cache 2> /dev/null
 
-  bkupDir=/tmp/backup-pre-${VERSION}
+  bkupDir=backup-pre-${VERSION}
   # fixup any previous interrupted upgrades
   rm -rf "${bkupDir}"
   for d in behavior_packs definitions minecraftpe resource_packs structures treatments world_templates
@@ -96,11 +96,6 @@ if [ ! -f "bedrock_server-${VERSION}" ]; then
       mv $d $bkupDir
     fi
   done
-  # remove any old  previous backups
-  shopt -s nullglob
-  for d in backup-pre-*; do
-    rm -rf $d
-  done
 
   # Do not overwrite existing files, which means the cleanup above needs to account for things
   # that MUST be replaced on upgrade