The EmptyRootHash and EmptyCodeHash are defined everywhere in the codebase, this PR replaces all of them with unified one defined in core/types package, and also defines constants for TxRoot, WithdrawalsRoot and UncleRoot
* common, core, eth, les, trie: make prque generic
* les/vflux/server: fixed issues in priorityPool
* common, core, eth, les, trie: make priority also generic in prque
* les/flowcontrol: add test case for priority accumulator overflow
* les/flowcontrol: avoid priority value overflow
* common/prque: use int priority in some tests
No need to convert to int64 when we can just change the type used by the
queue.
* common/prque: remove comment about int64 range
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Co-authored-by: Zsolt Felfoldi <zsfelfoldi@gmail.com>
Co-authored-by: Felix Lange <fjl@twurst.com>
