melib/email: don't do case sensitive eq for mime parameters

melib/src/email.rs

@@ -280,7 +280,7 @@ impl Envelope {
                         builder.set_content_type_from_bytes(value);
                         let mut boundary = None;
                         for (n, v) in params {
-                            if n == b"boundary" {
+                            if n.eq_ignore_ascii_case(b"boundary") {
                                 boundary = Some(v);
                                 break;
                             }

melib/src/email/attachments.rs

@@ -390,7 +390,7 @@ impl fmt::Display for Attachment {
                 let name = String::from_utf8_lossy(
                     parameters
                         .iter()
-                        .find(|(name, _)| name == b"name")
+                        .find(|(name, _)| name.eq_ignore_ascii_case(b"name"))
                         .map(|(_, value)| value)
                         .unwrap(),
                 );