Reformat axis titles in mock

Author: hannahker

test/image/mocks/z-automargin-minreducedwidth.json

@@ -3,10 +3,10 @@
             "name": "< D E A T H >",
             "marker": { "color": "red" },
             "y": [
-                "Antonio Vivaldi but even longer",
-                "Johann Sebastian Bach but even longer",
-                "Wolfgang Amadeus Mozart but even longer",
-                "Ludwig van Beethoven but even longer"
+                "A n t o n i o   V i v a l d i",
+                "J o h a n n   S e b a s t i a n   B a c h",
+                "W o l f g a n g   A m a d e u s   M o z a r t",
+                "L u d w i g   v a n   B e e t h o v e n"
             ],
             "x": [
                 "1741",
@@ -19,10 +19,10 @@
         "name": "< B I R T H >",
         "marker": { "color": "blue" },
         "y": [
-            "Antonio Vivaldi but even longer",
-            "Johann Sebastian Bach but even longer",
-            "Wolfgang Amadeus Mozart but even longer",
-            "Ludwig van Beethoven but even longer"
+            "A n t o n i o   V i v a l d i",
+            "J o h a n n   S e b a s t i a n   B a c h",
+            "W o l f g a n g   A m a d e u s   M o z a r t",
+            "L u d w i g   v a n   B e e t h o v e n"
         ],
         "x": [
             "1678",