Make PineconeHandler more efficient (fetch only fresher markets)

[gabrielfior]

224036c#diff-1b9d8df9eb7cb55918e642ebc0f26902d5211d4946a8c4d0454e9889dd05c371R124-R128

Instead of fetching all markets, fetch most recent market (based on close_time) and fetch only markets whose close_time >= max_close_time_from_pinecone).
Note that Pinecone Python's client does not have allow metadata-querying, hence some magic is required - see below

start_item_ids = handler.list_paginated(top_k=10) # fetch IDs
start_items = handler.query(ids=ids, include_metadata=True) # fetch top 10 items
max_market_close_time = max(start_item.close_time for start_item in start_item['matches'])
while True:
    # fetch new markets with filter close_time $gt max_market_close_time
    #. if items delivered = [], break