Update palimpsest to 2.0.0

[stephane-caron]

Although this PR only updates palimpsest to version 2, there is a major change in that version that directly impacts spine behaviors:

• Action dictionaries read by the spine are now fully logged (including keys not used by the spine itself)

As a consequence, we will be able to clear out asyncio loggers on the Python side, leaving the spine as the single source of truth for logs.

Performance regression check

foxplot([data.spine.clock.measured_period, data.spine.clock.slack], right=[data.spine.clock.skip_count])

Before

2023-10-16_185356_pi3hat_spine.mpack

After

2023-10-16_190040_pi3hat_spine.mpack

[coveralls]

Pull Request Test Coverage Report for Build 6537019066

• 21 of 24 (87.5%) changed or added relevant lines in 2 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.006%) to 87.885%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
vulp/spine/Spine.cpp	11	14	78.57%
<!--	Total:	21	24	87.5%	-->

Totals
Change from base Build 6420685880:	0.006%
Covered Lines:	1654
Relevant Lines:	1882

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💛 - Coveralls