windows preview bug fix

[José Matos]

On Fri, 2024-02-16 at 15:23 +0200, Idan Pazi wrote:
> Encountered the following bug (windows 10, python 3.12) - preview of
> math fails:
> >  graphics\PreviewLoader.cpp (2ef):
> > PreviewLoader::finishedInProgress(1): processing failed for py -3 -
> > tt $$s/scripts/lyxpreview2bitmap.py --png
> > "C:/Users/idank/AppData/Local/Temp/lyx_tmpdir.mzhGYGTpQcAc/lyx_tmpb
> > uf0/lyxpreviewuaCFJC.tex" --dpi 137 --fg 000000 --bg ffffff --
> > bibtex="bibtex"
> 
> 
> Running the command manually gives the problem:
> >   File "C:\Program Files\LyX
> > 2.4\Resources\scripts\lyxpreview_tools.py", line 168, in
> > run_command_win32
> >     data = data + buffer
> >            ~~~~~^~~~~~~~
> > TypeError: can only concatenate str (not "bytes") to str
> 
> 
> Apparently, the returned value from win32file.ReadFile should be
> converted to a string. 
> Fix patch attached.
> Thank you, Idan

After our exchange last week I feel inclined to apply this.

I am still note sure that this is the right step but clearly it
improves the code regarding the previous one.

Does any one opposes to this action?

Best regards,
-- 
José Abílio