since and before for stable versions do not consider the date of nightly build

[wmmc88]

According to the README, #[rustversion::since(1.74)] should be

True on that stable release and any later compiler, including beta and nightly.

The key word in this sentence is later. Stable Rust 1.74.0 was released on 2023-11-16, but nightly-2023-09-14 is a nightly that came out more than 2 months before. The following snippet succeeds to compile when it should fail because the nightly is older than 1.74:

#[rustversion::since(1.74)]
fn main() {
   println!("Hello, world!");
}

cargo +nightly-2023-09-13 b
   Compiling rustversion v1.0.14
   Compiling rust-version-test v0.1.0 (D:\git-repos\github\rust-version-test)
    Finished dev [unoptimized + debuginfo] target(s) in 2.26s

Similarly, the below snippet fails to compile on nightly-2023-09-14:

#[rustversion::before(1.74)]
fn main() {
    println!("Hello, world!");
}

cargo +nightly-2023-09-14 b
   Compiling rustversion v1.0.14
   Compiling rust-version-test v0.1.0 (D:\git-repos\github\rust-version-test)
error[E0601]: `main` function not found in crate `rust_version_test`
 --> src\main.rs:4:2
  |
4 | }
  |  ^ consider adding a `main` function to `src\main.rs`

For more information about this error, try `rustc --explain E0601`.
error: could not compile `rust-version-test` (bin "rust-version-test") due to previous error