liberia.svg: namespace errors
When liberia.svg is loaded to inkscape, it gives various namespace errors. This was once (2017) fixed by bringing in image from another source, but that was later reverted as having wrong aspect ratio.
However, it now seems that simply resaving the file will get us rid of those errors - as the loading of the offending entries has failed anyway, they are not there to be saved.
These are a bit more serious (or at least more rare in our flag images) errors than the ones usually handled in our master-only flag updates series - will target this to stable branches too.