Merge ~chad.smith/curtin:cleanup/1847138-time-drift-unittest-fix into curtin:master

[Chad Smith]

tests: mock timestamp used in collect-log file creation

The unittest for curtin collect-logs uses a timestamp to
create the filename for the tarball. The selected in the
unittest versus when the call occurs may race if the delay
between the calls is greater than 1 second. Resolve this
unittest issue by providing the same timestamp value.

LP: #1847138

[Ryan Harper (raharper)]

review: Approve

[Server Team CI bot (server-team-bot)]

PASSED: Continuous integration, rev:d7ca0ed0c3edcc64c303668368f699f4a312dbb1
https://jenkins.ubuntu.com/server/job/curtin-ci/3729/
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    SUCCESS: https://jenkins.ubuntu.com/server/job/curtin-ci/nodes=metal-ppc64el/3729/
    SUCCESS: https://jenkins.ubuntu.com/server/job/curtin-ci/nodes=metal-s390x/3729/
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review: Approve (continuous-integration)

diff --git a/tests/unittests/test_commands_collect_logs.py b/tests/unittests/test_commands_collect_logs.py
index 6b958f4..1feba18 100644
--- a/tests/unittests/test_commands_collect_logs.py
+++ b/tests/unittests/test_commands_collect_logs.py
@@ -298,7 +298,9 @@ class TestCreateTar(CiTestCase):
             'install': {'log_file': log1, 'post_files': [log2, absent_log]}}
         self.add_patch('shutil.copy', 'm_copy')
         with mock.patch('sys.stderr') as m_stderr:
-            collect_logs.create_log_tarfile(tarfile, config=config)
+            with mock.patch('curtin.commands.collect_logs.datetime') as m_dt:
+                m_dt.utcnow.return_value = self.utcnow
+                collect_logs.create_log_tarfile(tarfile, config=config)
         self.assertIn(
             mock.call(
                 'Skipping logfile %s: file does not exist\n' % absent_log),