remove tempdir on start

Bug: 76088091
Test: ./update_current.py -s 4675010

Change-Id: Ibfba5bc0fc4cf86edf33a8c2b93bdecdfdec90aa
diff --git a/update_current/update_current.py b/update_current/update_current.py
index 8315572..150279f 100755
--- a/update_current/update_current.py
+++ b/update_current/update_current.py
@@ -632,6 +632,7 @@
         return True
 
 
+rm(temp_dir)
 parser = argparse.ArgumentParser(
     description=('Update current prebuilts'))
 parser.add_argument(