Merge pull request swiftlang#32685 from compnerd/testing-the-future

test: migrate tests to Python3 by default

Author: shahmishal

test/CMakeLists.txt

@@ -351,7 +351,7 @@ _Block_release(void) { }\n")
       endif()
 
       execute_process(COMMAND
-          $<TARGET_FILE:Python2::Interpreter> "-c" "import psutil"
+          $<TARGET_FILE:Python3::Interpreter> "-c" "import psutil"
           RESULT_VARIABLE python_psutil_status
           TIMEOUT 1 # second
           ERROR_QUIET)
@@ -415,7 +415,7 @@ _Block_release(void) { }\n")
             ${command_upload_swift_reflection_test}
             ${command_clean_test_results_dir}
             COMMAND
-              $<TARGET_FILE:Python2::Interpreter> "${LIT}"
+              $<TARGET_FILE:Python3::Interpreter> "${LIT}"
               ${LIT_ARGS}
               "--param" "swift_test_subset=${test_subset}"
               "--param" "swift_test_mode=${test_mode}"
@@ -434,7 +434,7 @@ _Block_release(void) { }\n")
             ${command_upload_swift_reflection_test}
             ${command_clean_test_results_dir}
             COMMAND
-              $<TARGET_FILE:Python2::Interpreter> "${LIT}"
+              $<TARGET_FILE:Python3::Interpreter> "${LIT}"
               ${LIT_ARGS}
               "--param" "swift_test_subset=${test_subset}"
               "--param" "swift_test_mode=${test_mode}"