fix: fix potential concurrent access on StorageElector::curr_leader_host

[dyinnz]

Changelog category

• Bug Fix

Changelog entry (a user-readable short description of the changes that goes to CHANGELOG.md):

[fix](fix: fix potential concurrent access on StorageElector::curr_leader_host)

This is not a real bug. But curr_leader_host shall be protected by a mutex, while it is not acquired inside StorageElector::setRole().

[CLAassistant]

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[yuanzhubi]

Why it is needed? Only the bg_thread of the StorageElector object is enabled to update the role.

[dyinnz]

Why it is needed? Only the bg_thread of the StorageElector object is enabled to update the role.

yes, this is not needed in fact. Your word is correct, but other coders would not get the point at once after reading the piece of codes, which I mean, may need some logical inference. Or you could comment some notes on the curr_leader_host accessing where lacked lock protection.