test: update mock bar_attrs_group_norm

* Set outside font size to 32 to force rotation. This change will test
  that horizontal bars rotate the bar text clockwise or anti-clockwise
  as appropriate.

Author: n-riesco

test/image/mocks/bar_attrs_group_norm.json

@@ -2,13 +2,14 @@
     "data":[
         {
             "text":[100,125,150,175],
-	    "textposition":"outside",
+            "textposition":"outside",
+            "outsidetextfont": {"size":32},
             "base":4,
             "x":[3,2,1,0],
             "type":"bar"
         }, {
             "text":[100,125,150,175],
-	    "textposition":"inside",
+            "textposition":"inside",
             "base":[7,6,5,4],
             "x":[1,2,3,4],
             "type":"bar"