When many text using BLF the glymp texture could be re-written. In this case the new upload should be done in a separate render graph node group. This wasn't the case and resulted in validation warnings about the glyph texture being in an layout that wasn't expected. This PR simplifies the group extraction a bit by looking ahead when the group ends. Pull Request: https://projects.blender.org/blender/blender/pulls/123547