DAOS-14072 test: fix regression with DmgPoolQueryTest (#12733)

The SCM size of a pool depends of the number of targets.  The commit
27b50c1 of the ticket DAOS-13380 has
updated the number of targets without updating the SCM size of the
resulting pool.

Signed-off-by: Cedric Koch-Hofer <cedric.koch-hofer@intel.com>

src/tests/ftest/control/dmg_pool_query_test.yaml

@@ -33,7 +33,7 @@ exp_vals:
   version: 1
   leader: 0
   scm:
-    total: 16000024576
+    total: 16000008192
   nvme:
     total: 32000000000
   rebuild: