Use timezone-aware objects to represent datetimes in UTC.

[fujitatomoya]

address following deprecation warnings.

root@tomoyafujita:~/ros2_ws/colcon_ws# colcon test --event-handlers console_direct+ --packages-select sros2
...
=============================== warnings summary ===============================
test/test_flake8.py: 16 warnings
  Warning: This process (pid=242453) is multi-threaded, use of fork() may lead to deadlocks in the child.

test/sros2/commands/security/verbs/test_create_enclave.py: 10 warnings
test/sros2/commands/security/verbs/test_create_keystore.py: 4 warnings
test/sros2/commands/security/verbs/test_create_permission.py: 5 warnings
test/sros2/commands/security/verbs/test_generate_artifacts.py: 24 warnings
test/sros2/commands/security/verbs/test_list_enclaves.py: 10 warnings
test/sros2/keystore/test_enclave.py: 2 warnings
  Warning: datetime.datetime.utcnow() is deprecated and scheduled for removal in a future version. Use timezone-aware objects to represent datetimes in UTC: datetime.datetime.now(datetime.UTC).

-- Docs: https://docs.pytest.org/en/stable/how-to/capture-warnings.html
------ generated xml file: /root/ros2_ws/colcon_ws/build/sros2/pytest.xml ------
================= 35 passed, 71 warnings in 122.06s (0:02:02) ==================
--- stderr: sros2

=============================== warnings summary ===============================
test/test_flake8.py: 16 warnings
  Warning: This process (pid=242453) is multi-threaded, use of fork() may lead to deadlocks in the child.

test/sros2/commands/security/verbs/test_create_enclave.py: 10 warnings
test/sros2/commands/security/verbs/test_create_keystore.py: 4 warnings
test/sros2/commands/security/verbs/test_create_permission.py: 5 warnings
test/sros2/commands/security/verbs/test_generate_artifacts.py: 24 warnings
test/sros2/commands/security/verbs/test_list_enclaves.py: 10 warnings
test/sros2/keystore/test_enclave.py: 2 warnings
  Warning: datetime.datetime.utcnow() is deprecated and scheduled for removal in a future version. Use timezone-aware objects to represent datetimes in UTC: datetime.datetime.now(datetime.UTC).

-- Docs: https://docs.pytest.org/en/stable/how-to/capture-warnings.html
---
Finished <<< sros2 [2min 4s]

Summary: 1 package finished [2min 6s]
  1 package had stderr output: sros2

Note

even with this PR, there are still same warnings come up. i think these are from dependent modules, because there is nowhere else sros2 uses deprecated API.

[fujitatomoya]

Pulls: #341
Gist: https://gist.githubusercontent.com/fujitatomoya/7077f1acb89710aca47c9777b162d9ca/raw/7c80a3d4cf77201536a58977fd2635a5ce8d01c9/ros2.repos
BUILD args: --packages-above-and-dependencies sros2
TEST args: --packages-above sros2
ROS Distro: rolling
Job: ci_launcher
ci_launcher ran: https://ci.ros2.org/job/ci_launcher/15919

• Linux
• Linux-aarch64
• Linux-rhel
• Windows

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 88.94%. Comparing base (59fe530) to head (9ef5948).
Report is 2 commits behind head on rolling.

Additional details and impacted files

@@           Coverage Diff            @@
##           rolling     #341   +/-   ##
========================================
  Coverage    88.94%   88.94%           
========================================
  Files           24       24           
  Lines          615      615           
  Branches        64       64           
========================================
  Hits           547      547           
  Misses          50       50           
  Partials        18       18           

Flag	Coverage Δ
unittests	88.94% <ø> (ø)

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[mikaelarguedas]

thanks @fujitatomoya , this looks similar in purpose as #300 that removes every use of utcnow in sros2.
Any chance to get #300 tested for integration into kilted ? 🙏

[fujitatomoya]

@mikaelarguedas thanks for the info! let's work on #300