src/mon/ConnectionTracker.cc: fix dump

src/mon/ConnectionTracker.cc: fix dump

Problem:

Currently, the ConnectionTracker::dump()
will dump a duplicate key which is not
ideal when you want to write a test that
converts the dump into a JSON since
JSON objects are key-value pairs where
each key must be unique.

Solution:
Use open_array_section and convert
`peer_scores` and `reports` into an
array instead.

Fixes: https://tracker.ceph.com/issues/65695
Signed-off-by: Kamoltat <ksirivad@redhat.com>