refactor: Fix a Rust 1.45 Clippy warning

[AzureMarker]

Original warning:

warning: using `Result.or_else(|x| Err(y))`, which is more succinctly expressed as `map_err(|x| y)`
  --> autoendpoint/src/settings.rs:63:9
   |
63 | /         config.try_into::<Self>().or_else(|error| match error {
64 | |             // Configuration errors are not very sysop friendly, Try to make them
65 | |             // a bit more 3AM useful.
66 | |             ConfigError::Message(error_msg) => {
...  |
79 | |             }
80 | |         })
   | |__________^
   |
   = note: `#[warn(clippy::bind_instead_of_map)]` on by default
   = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#bind_instead_of_map
help: try this
   |
63 |         config.try_into::<Self>().map_err(|error| match error {
64 |             // Configuration errors are not very sysop friendly, Try to make them
65 |             // a bit more 3AM useful.
66 |             ConfigError::Message(error_msg) => {
67 |                 println!("Bad configuration: {:?}", &error_msg);
68 |                 println!("Please set in config file or use environment variable.");
 ...