Cleanup: Fix capitalization in various UI strings

Approximately 195 changes of capitalization to conform to MLA title style.
UI labels and property names should use MLA title case, while descriptions
should be capitalized like regular prose, generally with only the start of
a sentence capitalized.

Differential Revision: https://developer.blender.org/D9922

release/scripts/startup/bl_ui/space_toolsystem_toolbar.py

@@ -1424,7 +1424,7 @@ class _defs_sculpt:
 
         return dict(
             idname="builtin.mask_by_color",
-            label="Mask By Color",
+            label="Mask by Color",
             icon="ops.sculpt.mask_by_color",
             widget=None,
             keymap=(),