fix: stores: Tune down StorageDeclareSector` log-lvl

[rjan90]

Related Issues

Closes: #10901

Proposed Changes

Tune down the log-level on StorageDeclareSector to debug.

Additional Info

Boost added an index integrity check in Boost 1.7.0 which causes users to see logs like these more often:

2023-05-22T13:51:13.217Z	WARN	stores	paths/index.go:369	sector {1278 997} redeclared in d8cfac01-4999-45d5-8231-8aa9423224e2

The WARN level here seems wrong as these are expected, and the interval of how often this gets called can be tuned in the configs on Boost.

I have added a KB-article explaining why users might see these logs as well here: https://lotus.filecoin.io/kb/redeclared-sector-log/

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