This patch adds tracking number of batches and tuples that needed
to be decompressed as part of DML operations on compressed hypertables.
These will be visible in EXPLAIN ANALYZE output like so:
QUERY PLAN
Custom Scan (HypertableModify) (actual rows=0 loops=1)
Batches decompressed: 2
Tuples decompressed: 25
-> Insert on decompress_tracking (actual rows=0 loops=1)
-> Custom Scan (ChunkDispatch) (actual rows=2 loops=1)
-> Values Scan on "*VALUES*" (actual rows=2 loops=1)
(6 rows)