Add trailing padding to preference panes

Xcodes/Frontend/Preferences/AdvancedPreferencePane.swift

@@ -68,6 +68,7 @@ struct AdvancedPreferencePane: View {
                 }
             }
         }
+        .padding(.trailing)
     }
     
     private var dataSourceFootnote: NSAttributedString {

Xcodes/Frontend/Preferences/GeneralPreferencePane.swift

@@ -29,6 +29,7 @@ struct GeneralPreferencePane: View {
                 }
             }
         }
+        .padding(.trailing)
     }
 }
 

Xcodes/Frontend/Preferences/UpdatesPreferencePane.swift

@@ -34,6 +34,7 @@ struct UpdatesPreferencePane: View {
                 .frame(maxWidth: .infinity, alignment: .leading)
             }
         }
+        .padding(.trailing)
     }
     
     private var lastUpdatedString: String {