fix Content-Type header missing for some error pages

- also add changelog entry for previous commit

Changelog.md

@@ -7,6 +7,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Fix
+- confirmation emails now set the UserAgent and Auto-Submitted headers
+- the error pages using the generic_error_handler now set the Content-Type header
+
 ## [0.2.0] (2022-06-09)
 
 ### Add

src/route/error_handler.rs

@@ -1,7 +1,7 @@
 use crate::auth::User;
 use crate::error::PresentationError;
 use crate::job_offers::error::SaveResponseError;
-use crate::route::LOGIN_ROUTE;
+use crate::route::{HTML_CONTENT, LOGIN_ROUTE};
 use crate::{route, ServerConfig};
 
 use crate::route::job_offer::edit::EditResponseError;
@@ -16,7 +16,7 @@ use actix_web::middleware::ErrorHandlerResponse;
 use actix_web::web::Data;
 use actix_web::{HttpRequest, HttpResponse, ResponseError};
 use handlebars::Handlebars;
-use http::header::LOCATION;
+use http::header::{CONTENT_TYPE, LOCATION};
 use http::Method;
 use lettre::address::AddressError;
 use log::{error, warn};
@@ -54,9 +54,14 @@ pub(crate) fn generic_server_error_handler<B>(
         .render(template, &data)
         .map_err(PresentationError::Render)?;
 
-    let response = HttpResponse::with_body(res.status(), body)
+    let mut response = HttpResponse::with_body(res.status(), body)
         .map_into_boxed_body()
         .map_into_right_body();
+
+    response
+        .headers_mut()
+        .insert(CONTENT_TYPE, HTML_CONTENT.clone());
+
     let response = res.into_response(response);
 
     Ok(ErrorHandlerResponse::Response(response))