* fix logic issue: handlers.removePeer() is called twice.
There is a logic issue which cause "Ethereum peer removal failed, err=peer not registered" occur quite often.
handler.runEthPeer set up a defer removePeer(). This is always called after a peer is disconnected.
However removePeer is also called by mulitple functions like downloader/fetcher. After those kind of functions removePeer(), peer handler executes defer removePeer(). This makes removePeer() happened twice, and this is the reason we often see "Ethereum peer removal failed, err=peer not registered".
To solve this, removePeer only needs to hard Disconnect peer from networking layer. Then defer unregisterPeer() will do the cleanup task after then.
* fix: modify test function for close testing.
reference from go-thereum.
Co-authored-by: zjubfd <296179868@qq.com>
15bc2548c1