FIX: removed whitespaces from generated csv files to improve Excel compability

src/modules/api/events/update.rs

@@ -262,7 +262,7 @@ pub async fn approve(
                 };
                 debug!("Generated CSV: {}", csv);
                 if settings.billing.send_personnel_billing_to_email {
-                    let attachement = Attachment::new(String::from("Einsatzabrechnung.csv")).body(csv, ContentType::parse("text/csv").unwrap());
+                    let attachement = Attachment::new(String::from("Einsatzabrechnung.txt")).body(csv, ContentType::parse("text/csv").unwrap());
                     let msg = Message::builder()
                         .from(settings.mail.from.clone().parse().unwrap())
                         .reply_to(settings.mail.reply_to.clone().parse().unwrap())

src/modules/event_billing/generate_billing_csv.rs

@@ -97,7 +97,7 @@ pub fn generate_billing_csv(settings: &State<Settings>, event_id: uuid::Uuid) ->
         }
     }
 
-    res.push_str("\n");
+    res.push('\n');
 
     let instances = get_instances(settings, event_id)?;
 
@@ -135,7 +135,7 @@ pub fn generate_billing_csv(settings: &State<Settings>, event_id: uuid::Uuid) ->
                 };
             }
         }
-        res.push_str("\n");
+        res.push('\n');
     }
     Ok(res)
 }