fix(blooms): Fix eviction of multiple blockcache items

[chaudum]

What this PR does / why we need it:

This commit fixes a bug in the eviction of least recently used items. When an element from the doubly-linked-list of the cache is removed, then the element's prev and next items become nil. Therefore the call elem.Prev() always broke the loop's condition for checking entries to be evicted.

Checklist

• Reviewed the CONTRIBUTING.md guide (required)
• Documentation added
• Tests updated
• Title matches the required conventional commits format, see here
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[cyriltovena]

LGTM