Stop using CONCURRENTLY when creating indexes

CONCURRENT indexes are only valid if they are not created inside a
transaction block.

psycopg2 has started to automatically emit BEGIN / END transaction when
using the "with "  context manager, thus causing explicit transactions
to happen for us here.

See: psycopg/psycopg2#941

This means that we now need to stop using concurrently as we may or may
not be inside a transaction block.

housekeeper/housekeeper.py

@@ -55,20 +55,19 @@ def clean_old_indexes(table="history", year=2011, month=12):
             yield cleanup.format(oldindex)
 
 
-def ensure_btree_index(table="history", year=2011, month=12, concurrently=True):
+def ensure_btree_index(table="history", year=2011, month=12):
     index = get_index_name(table=table, year=year, month=month, kind="btree")
     table = get_table_name(table=table, year=year, month=month)
-    conc = "CONCURRENTLY" if concurrently else ""
     with log_state(step="ensure_btree_index", table=table, index=index):
-        yield f"CREATE INDEX {conc} IF NOT EXISTS {index} on {table} using btree (itemid, clock);"
+        yield f"CREATE INDEX IF NOT EXISTS {index} on {table} using btree (itemid, clock);"
 
 
 def ensure_brin_index(table="history", year=2011, month=12):
     index = get_index_name(table=table, year=year, month=month, kind="brin")
     table = get_table_name(table=table, year=year, month=month)
     with log_state(step="ensure_brin_index", index=index, table=table):
         yield (
-            f"CREATE INDEX CONCURRENTLY IF NOT EXISTS {index} on {table} "
+            f"CREATE INDEX IF NOT EXISTS {index} on {table} "
             f"USING brin (itemid, clock) WITH (pages_per_range='16');"
         )
 

housekeeper/partition.py

@@ -10,7 +10,7 @@ def gen_partitions(table="history_part"):
         )
 
         yield from ensure_btree_index(
-            table=table, year=date.year, month=date.month, concurrently=False
+            table=table, year=date.year, month=date.month
         )