### Description
Update NDK to 26.0.10792818 which is included in every macOS build
machine so that we do not need to download a different version every
time in every build.
### Motivation and Context
Downloading NDK on-the-fly is a main contributor of Android related
build failures.
Here's the motivating issue:
https://github.com/microsoft/azure-pipelines-tasks/issues/10331
Noticed some problems in other repos so also updating usages in ORT.
We may be fine now without it, but this change adds some safeguard against future additions of 'set -x' for debugging.
Current builds use a NDK version that happens to be on the build machine. The build machine environment may change in ways that are outside of our control.
This change installs a specific version of NDK (the current LTS version 25.0.8775105) and uses it.
