Some Friendly Advice
Who knows when the next DLC will come, 3 months, 6 months, never?
This is a great time to backup. Create a folder, perhaps called GTA5 Back July 2021.
In it put your GTA5.exe files (they are small so err on side of all of the .exes). Put in the update.rpf from your MODS folder (great idea to always have a backup of this file).
Also put in a copy of the July 23rd 2021 ScriptHook.
That's all you need. Remember that your Mods folder, your addons/dlcpacks etc will not be harmed by the update - but good idea to keep these backed up as well given it takes time to install them, modify them, and ofc they are often removed by the author completely from this site and others.
N.B. For this particular update, at least for Steam, I was able to play modded SP by only restoring 1 file, GTA5.exe.
However that could change with a future DLC, so again backup whatever you think might be useful. You don't need to copy those huge rpf files in the games folder.