cheets_CTS_R: Mark control files as Python3-ready.

BUG=b:195470430
TEST=cheets_CTS_R.arm.waivers run without issues

Change-Id: I1bbf79c64f6c31a5f866ac972eb90b13600ef0d9
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/autotest/+/3261455
Commit-Queue: Kazuhiro Inaba <[email protected]>
Commit-Queue: Jiyoun Ha <[email protected]>
Tested-by: Kazuhiro Inaba <[email protected]>
Auto-Submit: Kazuhiro Inaba <[email protected]>
Reviewed-by: Jiyoun Ha <[email protected]>
diff --git a/server/site_tests/cheets_CTS_R/control.x86.CtsTelecomTestCases2 b/server/site_tests/cheets_CTS_R/control.x86.CtsTelecomTestCases2
index 39cdaf0..de94a35 100644
--- a/server/site_tests/cheets_CTS_R/control.x86.CtsTelecomTestCases2
+++ b/server/site_tests/cheets_CTS_R/control.x86.CtsTelecomTestCases2
@@ -12,6 +12,7 @@
 TEST_TYPE = 'server'
 TIME = 'MEDIUM'
 MAX_RESULT_SIZE_KB = 512000
+PY_VERSION = 3
 DOC = 'Run module CtsTelecomTestCases2 of the Android Compatibility Test Suite (CTS) using x86 ABI in the ARC++ container.'
 
 def run_TS(machine):