Update configure script to not warn about Bazel r17 and r18. Bazel supports both revisions now.

PiperOrigin-RevId: 221145880
diff --git a/configure.py b/configure.py
index 2d2bcd8..234561d 100644
--- a/configure.py
+++ b/configure.py
@@ -43,7 +43,7 @@
 _TF_OPENCL_VERSION = '1.2'
 _DEFAULT_COMPUTECPP_TOOLKIT_PATH = '/usr/local/computecpp'
 _DEFAULT_TRISYCL_INCLUDE_DIR = '/usr/local/triSYCL/include'
-_SUPPORTED_ANDROID_NDK_VERSIONS = [10, 11, 12, 13, 14, 15, 16]
+_SUPPORTED_ANDROID_NDK_VERSIONS = [10, 11, 12, 13, 14, 15, 16, 17, 18]
 
 _DEFAULT_PROMPT_ASK_ATTEMPTS = 10