[MINOR] Docs: remove incubator words

- Docs: remove incubator words

Author: Hao Chen <hchen9@ebay.com>

Closes #967 from haoch/removeIncubatorWords.

(cherry picked from commit 93095296a16a72986e04a9f720fc8d5a28a181fb)
Signed-off-by: Hao Chen <hchen9@ebay.com>
1 file changed