Fix: Change input to allow embedded refs

Fix: Change input to allow embedded refs

Change the single-quoted string to double quotes
to allow embedded references to variables without
which the credentials files do not get created under
$HOME.

Error:
[ERROR] failed to expand variables in target location
'$HOME/.aws/credentials' : Error processing tokens
copy managed file [jenkins-s3-log-ship] to
file:/w/workspace/aaa-ci-pipeline_70_101670_21/$HOME/
.aws/credentials

Update the test to add $HOME mock variable.

Issue-ID: RELENG-4327
Signed-off-by: Anil Belur <abelur@linuxfoundation.org>
Change-Id: I8019d0c0bc9aa3eacf8eb902e33102271de303bb
Signed-off-by: Anil Belur <abelur@linuxfoundation.org>