Fix font filename when font variant is missing

[jesuslg123]

Fix invalid font name when the font variant is missing on the OSD file.
It was creating a font_.png file name which was invalid.

[j005u]

@jesuslg123 can you also bump the version number to 2.3.1 please?
@stylesuxx remind me please, what was the procedure for pushing things to the develop preview hosting? Merge into develop branch? Did it also need a tag?

[stylesuxx]

@j005u merging it into develop should deploy it on the develop branch.

Creating a news release (I use git flow) will merge develop into master and that should then deploy to prod. So I'd adjust the base branch to develop and merge that. Test on develop and if everything works as expected merge into master.

I can do that today in the evening...

[j005u]

@jesuslg123 so can you please change the PR base branch (in GH UI) to "develop" instead of "master". Then @stylesuxx can deploy it to the testing version of the configurator.

[stylesuxx]

I can change the base branch too, no worries...

[jesuslg123]

@stylesuxx feel free to resolve the conflict with the version you prefer please I am afk for today

[j005u]

@stylesuxx while this wasn't the main issue users were having it does also solve an edge case in relation to .osd recordings from audience mode. Confirmed working, let's release it.

[stylesuxx]

@j005u will do, I'll merge translation updates too. I am not 100% sure if I can make it today though - latest tomorrow.