This isn't sequencing... you'd use sequencing to identify novel mutations or strains of the virus. This is a set of known PCR primers that amplify the virus's RNA. You could (in theory) also use a similar approach to identify specific strains of the virus, but this shouldn't be the priority at the moment.
While you could have an assay that used sequencing, it wouldn't be nearly as fast or cost efficient.
This CDC document was an interesting read. I found this part particularly fascinating.
>RNA isolated and purified from upper and lower respiratory specimens is reverse transcribed to cDNA
and subsequently amplified in the Applied Biosystems 7500 Fast Dx Real-Time PCR Instrument with SDS
version 1.4 software. In the process, the probe anneals to a specific target sequence located between
the forward and reverse primers. During the extension phase of the PCR cycle, the 5’ nuclease activity
of Taq polymerase degrades the probe, causing the reporter dye to separate from the quencher dye,
generating a fluorescent signal. With each cycle, additional reporter dye molecules are cleaved from
their respective probes, increasing the fluorescence intensity. Fluorescence intensity is monitored at
each PCR cycle by Applied Biosystems 7500 Fast Dx Real-Time PCR System with SDS version 1.4
software.
While you could have an assay that used sequencing, it wouldn't be nearly as fast or cost efficient.