[iquery][docs] Make example output consistent

This makes the example `cat` output consistent between two
example iterations.

TEST=none, just docs

Change-Id: Ib92f3043b0b50c649805da5f5119d78e42eed15f

garnet/docs/inspect/iquery.md

@@ -51,8 +51,8 @@ a/b/.channel
 
 $ iquery --cat a
 a:
-  key = value
-  key2 = 3.4
+  a_key = a_value
+  a_key2 = 3.4
 
 $ iquery --cat --recursive a
 a: