Cracks in Walk-out Basement Slab
The cracks in your slab have nothing to do with the plumbing repair. Slabs crack. Period. Typically the only question is how the cracks are managed. The slab should've been cut to create control joints, or "zip strips" should've been worked into the surface to direct where cracks occur. 

Now, if you have regular movement in the slab, that's a matter of poor compaction, excess unaddressed groundwater, or something else. That's a bigger problem that you'll need to discuss with the builder. 

If there's no movement, and depending on your choice of flooring, this isn't an issue. If you're going with ceramic tile, the installer will need to deal with the cracks appropriately. Other types of flooring will simply span over the cracks.