Static variables should have an upper case name
Static variables should have an upper case name

Fixed two warnings from the compiler:
```
warning: static variable `show_spinner` should have an upper case name such as `SHOW_SPINNER`, #[warn(non_upper_case_globals)] on by default
  --> src/delivery/utils/say.rs:27:1
   |
27 | static mut show_spinner: bool = true;
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

warning: static variable `show_output` should have an upper case name such as `SHOW_OUTPUT`, #[warn(non_upper_case_globals)] on by default
  --> src/delivery/utils/say.rs:28:1
   |
28 | static mut show_output:  bool = true;
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
```

Signed-off-by: Salim Afiune <2b0aff3923bd0ab6bbf45ffb37e57dcea8e1b0b8@chef.io>

chef/delivery-cli,chef/delivery-cli,chef/delivery-cli