LU-17322 auster: move functions to test-framework.sh

LU-17322 auster: move functions to test-framework.sh

auster is essentially a wrapper around
test-framework.sh. It's more sensible for functions
to be defined in the test library rather than a test
wrapper. A comment in auster even suggests this.

This small refactor will make it easier to write
alternative testing wrappers.

Test-Parameters: trivial
Signed-off-by: Timothy Day <timday@amazon.com>
Change-Id: Ia10a44396f81f0423c9c15cc9779658292bc739f
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/53271
Tested-by: Oleg Drokin <green@whamcloud.com>
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>