Store the order of Matrix blocks in a single Project Config file

[aaronbushnell]

Currently the order of the Matrix blocks for a given Matrix field is dictated by each blocks' sortOrder value. If you were to...

1. Drag the last block of a Matrix field to the top
2. Save the field

...Project Config will need to make an update to each of the files within config/project/matrixBlockTypes to set the new order. This can make reviewing a pull request with a reorder change quite daunting because all files will be touched by this update.

If the order of these blocks were set in a single file, like a new config/project/matrixOrder/my-matrix-field-[uuid].yaml file, it would greatly limit the number of modified files during a sort update and would limit merge conflicts as this only changes when sort order is modified.