Log Message:
tex-l3packages{,-doc}: update to 2023.69992

### Changed
- Re-added `\IfInstanceExist(TF)` to docs - is required

### Changed
- Preparation for move of `xtemplate` concepts to the kernel

### Removed
- `\IfInstanceExist(TF)`
- `xfrac`: moved to https://github.com/latex3/xfrac

### Changed
- Track `expl3` changes