[roll] Roll fuchsia [starnix] Show ZX_INFO_MEMORY_STALL info in /proc/pressure/memory

This CL makes starnix generate /proc/pressure/memory with real
stats, including averages over the last 10/60/300 seconds, that
are computed by Starnix according to data periodically sampled
from Zircon.

The a dedicated service (child of the Starnix runner) is
responsible for keeping track of the averages and, in general,
mediate access to the new PSI services. This provides an injection
point for test. Indeed, a new integration test uses this method
to feed known data to a puppet program running within Starnix
instance and verify that it gets back the expected readings.

Note: The ProcfsTest.ProcPressure test is now embedded in the new
integration test, which tests the cpu and io PSI files too (the
expectation being that in the future they will also be served
over the same protocol, like memory PSI is today).

Original-Bug: 319649348
Original-Reviewed-on: https://fuchsia-review.googlesource.com/c/fuchsia/+/1176632
Original-Revision: c792ba7fffb2e412ba50fd818ea2a2cd4e736a80
GitOrigin-RevId: f93201b35645dc853657ffcc753ecb601557761a
Change-Id: Ia45c7208b7e3c9b5b209b104da28590ca5247a0b

Author: Fabio D'Urso

stem

@@ -11,7 +11,7 @@
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-             revision="f32448fe89d38228aa067544d64b3f172e75f37a"/>
+             revision="c792ba7fffb2e412ba50fd818ea2a2cd4e736a80"/>
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