Rename argument in pg_get_process_memory_contexts().

During development the third argument to pg_get_process_memory_contexts
was a retry count, but it was changed to a timeout instead.  The param
name was accidentally left in pg_proc.dat though.  Fix by renaming to
the correct parameter name.

Author: Fujii Masao <masao.fujii@oss.nttdata.com>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Discussion: https://postgr.es/m/3eb40b3e-45c7-426a-b7f8-81f7d05a9b53@oss.nttdata.com

Author: danielgustafsson

src/include/catalog/pg_proc.dat

@@ -8578,7 +8578,7 @@
   prorettype => 'record', proargtypes => 'int4 bool float8',
   proallargtypes => '{int4,bool,float8,text,text,text,_int4,int4,int8,int8,int8,int8,int8,int4,timestamptz}',
   proargmodes => '{i,i,i,o,o,o,o,o,o,o,o,o,o,o,o}',
-  proargnames => '{pid, summary, retries, name, ident, type, path, level, total_bytes, total_nblocks, free_bytes, free_chunks, used_bytes, num_agg_contexts, stats_timestamp}',
+  proargnames => '{pid, summary, timeout, name, ident, type, path, level, total_bytes, total_nblocks, free_bytes, free_chunks, used_bytes, num_agg_contexts, stats_timestamp}',
   prosrc => 'pg_get_process_memory_contexts' },
 
 # non-persistent series generator