fix(snapshot): fix flagging obsolete snapshots for snapshot properties mismatch

[hi-ogawa]

Description

• Closes obsolete snapshot reported when snapshot fails with toMatchSnapshot(propertes) #9984

This fix needs similar mechanism as poll snapshot from #9973, so I copied the code from there (namely probeExpectedSnapshot).

Splitting current SnapshotClient.assert into match + assert is picked up from custom matcher support PR #9973. This is minor cleanup for this PR alone, but just preparing for it.

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