[graphite] Rename text RenderSteps to make them clearer

Bug: skia:13118
Change-Id: I6eaef6b0b5628dfddfcf424c66f313630ed405c3
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/568047
Commit-Queue: Jim Van Verth <jvanverth@google.com>
Reviewed-by: Michael Ludwig <michaelludwig@google.com>
6 files changed