Move the airflow install files to /usr/local
We saw an error with the previous version of the airflow images, because the airflow user didn't have write access into their own home directory. This would have also affected all of the other user accounts.
For this reason, this commit moves the contents of what was /home/airflow/.local to the /usr/local hierarchy.
That re-enables write access for each user to their own home directory.
Bug: T375895