Fix network error on save with trailing whitespace

[PhotoNomad0]

Seeing network error on save with trailing spaces.

@elsylambert captured this screenshot:

[PhotoNomad0]

Note:
The core of this error is the assumption that after a save, that the file sha will update. But DCS is ignoring the trailing space when applying the patch, and so the file is not saved. I verified that there is a space added at the end of the line, but the change is not saved on DCS.

I could turn off the check for changed file sha to see if that causes problems with switching books.