Fix casting warnings

[cohoe]

 [WARNING]: The value ['<Super>l', 'XF86ScreenSaver'] (type list) in a string field was converted to "['<Super>l',
'XF86ScreenSaver']" (type string). If this does not look like what you expect, quote the entire value to ensure it does not
change.

 [WARNING]: The value ['<Shift>Print'] (type list) in a string field was converted to "['<Shift>Print']" (type string). If
this does not look like what you expect, quote the entire value to ensure it does not change.

 [WARNING]: The value ['Print'] (type list) in a string field was converted to "['Print']" (type string). If this does not
look like what you expect, quote the entire value to ensure it does not change.

 [WARNING]: The value ['b1dcc9dd-5262-4d8d-a863-c897e6d979b9'] (type list) in a string field was converted to
"['b1dcc9dd-5262-4d8d-a863-c897e6d979b9']" (type string). If this does not look like what you expect, quote the entire value
to ensure it does not change.

 [WARNING]: The value ['x-content/unix-software', 'x-content/bootable-media'] (type list) in a string field was converted to
"['x-content/unix-software', 'x-content/bootable-media']" (type string). If this does not look like what you expect, quote
the entire value to ensure it does not change.

 [WARNING]: The value ['x-content/bootable-media'] (type list) in a string field was converted to "['x-content/bootable-
media']" (type string). If this does not look like what you expect, quote the entire value to ensure it does not change.

[cohoe]

 [WARNING]: The value of the "source" option was determined to be "pull". Please set the "source" option explicitly.
Autodetection will be removed in Ansible 2.12.

[cohoe]

All over security/sshd.