replace deprecated options and small code cleanup

[tcraxs]

I fix the following deprecation warnings:

TASK [jenkins : Install OS Dependencies]
[DEPRECATION WARNING]: Invoking "apt" only once while using a loop via
squash_actions is deprecated. Instead of using a loop to supply multiple items
and specifying `name: "{{ item }}"`, please use `name: ['apt-transport-https']`
and remove the loop. This feature will be removed in version 2.11.
[DEPRECATION WARNING]: State 'installed' is deprecated. Using state 'present'
instead.. This feature will be removed in version 2.9.

TASK [jenkins : Update Plugins]
[DEPRECATION WARNING]: evaluating jenkins_plugins_update as a bare variable,
this behaviour will go away and you might need to add |bool to the expression
in the future. Also see CONDITIONAL_BARE_VARS configuration toggle.. This
feature will be removed in version 2.12.

TASK [jenkins : Configure Jenkins (Miscellaneous Settings)]
[DEPRECATION WARNING]: Using tests as filters is deprecated. Instead of using
`result|success` use `result is success`. This feature will be removed in
version 2.9.

TASK [jenkins : Configure Security Recommendations] 
[DEPRECATION WARNING]: Using tests as filters is deprecated. Instead of using
`result|success` use `result is success`. This feature will be removed in
version 2.9.

• also fix some old syntax and whitespace