Update NDK to r18b, as that's what's in Pipelines.

Author: BillyONeal

Build_android/configure.sh

@@ -13,7 +13,7 @@
 
 set -e
 
-# The Android NDK r10e or later may work, but we test with r17c. To download, see the following link:
+# The Android NDK r10e or later may work, but we test with r18b. To download, see the following link:
 # https://developer.android.com/ndk/downloads/index.html
 
 # -----------------
@@ -24,7 +24,7 @@ DO_BOOST=1
 DO_OPENSSL=1
 DO_CPPRESTSDK=1
 
-BOOSTVER=1.65.1
+BOOSTVER=1.68.0
 OPENSSLVER=1.0.2k
 
 API=15