[graphite] remove 'testPrecompile' from Graphite config options

Change-Id: I2f8c35c6d65d73f2778c3a8f32d7cfb823a64d2c
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/546199
Reviewed-by: Greg Daniel <egdaniel@google.com>
Commit-Queue: Robert Phillips <robertphillips@google.com>
4 files changed