needless_doctest_main false positive with ```txt #5280
Description
This piece of documentation triggers the lint
/// ```txt
/// 1 | fn main() {
/// | __ ^
/// | _________|_|
/// | | |
/// | | this is a pair of parenthesis
/// 2 | | println!("Hello World!")
/// | | |^^^^^^^^^^^^^^| this is a pair of parenthesis
/// | | |_____________||
/// | | |
/// | | this is a string. Hard to see where it starts, uh?
/// 3 | | }
/// | |_^ this is a pair of braces
/// ```
warning: needless `fn main` in doctest
--> src/fmt.rs:207:4
|
207 | /// 1 | fn main() {
| ^^^^^^^^^^^^^^^^^^
|
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_doctest_main