Add missing displayTime formatter

FreeAPS/Sources/Models/BasalProfileEntry.swift

@@ -17,6 +17,10 @@ extension BasalProfileEntry {
         case rate
     }
 
+    var displayTime: String {
+        String(start.prefix(5))
+    }
+
     init(from decoder: Decoder) throws {
         let container = try decoder.container(keyedBy: CodingKeys.self)
         let start = try container.decode(String.self, forKey: .start)