For every peer expose through `getpeerinfo` RPC whether or not we selected them as HB peers, and whether or not they selected us as HB peers.

Suggestion by @gmaxwell.
#include <net_processing.h>
#include <addrman.h>
#include <banman.h>
#include <blockencodings.h>
#include <blockfilter.h>
#include <chainparams.h>
#include <consensus/validation.h>
#include <hash.h>
#include <index/blockfilterindex.h>
#include <merkleblock.h>
#include <netbase.h>
#include <netmessagemaker.h>
#include <policy/fees.h>
#include <policy/policy.h>
#include <primitives/block.h>
#include <primitives/transaction.h>
#include <random.h>
#include <reverse_iterator.h>
#include <scheduler.h>