Grating couplers - incorrect cell names, and wrong orientation

[lukasc-ubc]

The Grating Coupler cells that are in the SiEPIC_EBeam_PDK are:

And they are all oriented to face to the right when instantiated with no rotation:

We perform IP replacement prior to tape-out.

It seems that the gdsfactory grating couplers are incorrectly rotated, which after replacement leads to a non-functional circuit. See SiEPIC/openEBL-2024-10#172

@joamatab
@lbelangers