OCR model update We have updated the "builtin/latest" OCR model with quality improvements

## Change **OCR model update** We have updated the "builtin/latest" OCR model with quality improvements. Consequently, customers can continue to test this model for 90 _additional_ days. Please note that you have 90 days from today to test the new model by specifying "builtin/latest" in the model field of the [Feature](https://cloud.google.com/vision/docs/reference/rest/v1/Feature) object. At the end of that period, it will be promoted to the default model accessible as "builtin/stable". After that event, the original models will still be available for another 90 days using "builtin/legacy". If you encounter problems with this upgrade, please contact Vision API engineering team by submitting a ticket in the [private issue tracker](https://issuetracker.google.com/issues/new?component=491447). For the original announcement of this change, see the [October 1, 2021](https://cloud.google.com/vision/docs/release-notes#October%5F01%5F2021) release note. Region forwarding from the global to the regional endpoint has been deprecated. For more information, see the [October 1, 2021](https://cloud.google.com/vision/docs/release-notes#October%5F01%5F2021) release note.