fix_flaky_force_mode_test (backport #1429)

[mergify]

Fix time reference for force_mode_test

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This is an automatic backport of pull request #1429 done by Mergify.

[mergify]

Cherry-pick of 0d5d77e has failed:

On branch mergify/bp/humble/pr-1429
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Unmerged paths:
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	both modified:   ur_robot_driver/test/integration_test_force_mode.py

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