Remove __future__ import from cts scripts

The scripts are already using Python 3. No need to support Python 2.

BUG=chromium:1031760
TEST=None

Change-Id: Ifba8de3cf12081c0c2e3bc3a471ad257423501da
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/crostestutils/+/1959083
Tested-by: Greg Edelston <gredelston@google.com>
Reviewed-by: Rohit Makasana <rohitbm@chromium.org>
Reviewed-by: Aviv Keshet <akeshet@chromium.org>
Commit-Queue: Greg Edelston <gredelston@google.com>
diff --git a/provingground/cts/lib/upload_utils.py b/provingground/cts/lib/upload_utils.py
index fd3705a..d600a80 100755
--- a/provingground/cts/lib/upload_utils.py
+++ b/provingground/cts/lib/upload_utils.py
@@ -6,7 +6,6 @@
 
 """This script has helper methods to facilitate CTS/CTS-V upload."""
 
-from __future__ import print_function
 from subprocess import check_call
 
 import os
diff --git a/provingground/cts/upload_cts.py b/provingground/cts/upload_cts.py
index 2c23d06..6c3cab2 100755
--- a/provingground/cts/upload_cts.py
+++ b/provingground/cts/upload_cts.py
@@ -6,7 +6,6 @@
 
 """This script can be used to upload CTS results to CTS and APFE buckets."""
 
-from __future__ import print_function
 from lib.upload_utils import UploadUtils
 from xml.dom import minidom
 
diff --git a/provingground/cts/upload_cts_verifier.py b/provingground/cts/upload_cts_verifier.py
index 29e873c..7e59e83 100755
--- a/provingground/cts/upload_cts_verifier.py
+++ b/provingground/cts/upload_cts_verifier.py
@@ -6,7 +6,6 @@
 
 """This script uploads CTS Verifier results to CTS and APFE gs:// buckets."""
 
-from __future__ import print_function
 from lib.upload_utils import UploadUtils
 from xml.dom import minidom