Manual: fix bullet list indentation

Bug introduced in c4bf6d07.

(cherry picked from commit 65a5b211)

doc/manual/source/the-model-file.rst

@@ -9367,7 +9367,7 @@ Method of moments specific blocks
     * the first column contains the names of the endogenous variables
     * the second column contains the names of the exogenous variables
     * the third column contains a nested cell array that contains
-    the list of horizons, values and weights.
+      the list of horizons, values and weights.
 .. block:: matched_irfs_weights ;