avoid overflow of day depending of the month

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "wstunnel"
-version = "10.0.2"
+version = "10.0.1"
 edition = "2021"
 repository = "https://github.com/erebe/wstunnel.git"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html

src/embedded_certificate.rs

@@ -15,13 +15,13 @@ pub static TLS_CERTIFICATE: LazyLock<(Vec<CertificateDer<'static>>, PrivateKeyDe
     let el = now.elapsed();
     let year = 2024 - (el.as_nanos() % 2) as i32;
     let month = 1 + (el.as_nanos() % 12) as u8;
-    let day = 1 + (el.as_nanos() % 31) as u8;
+    let day = 1 + (el.as_nanos() % 28) as u8;
     cert.not_before = date_time_ymd(year, month, day);
 
     let el = now.elapsed();
     let year = 2024 + (el.as_nanos() % 50) as i32;
     let month = 1 + (el.as_nanos() % 12) as u8;
-    let day = 1 + (el.as_nanos() % 31) as u8;
+    let day = 1 + (el.as_nanos() % 28) as u8;
     cert.not_after = date_time_ymd(year, month, day);
 
     let cert = cert.self_signed(&key_pair).unwrap().der().clone();