remove unnecessary usings from solution, fixes in metrics

MareSynchronosServer/MareSynchronosShared/Metrics/MareMetrics.cs

@@ -29,7 +29,7 @@ public class MareMetrics
     {
         if (gauges.ContainsKey(gaugeName))
         {
-            gauges[gaugeName].IncTo(value);
+            gauges[gaugeName].Set(value);
         }
     }
 

MareSynchronosServer/MareSynchronosShared/Metrics/MetricsAPI.cs

@@ -1,6 +1,4 @@
-using StackExchange.Redis;
-
-namespace MareSynchronosShared.Metrics;
+namespace MareSynchronosShared.Metrics;
 
 public class MetricsAPI
 {

MareSynchronosServer/MareSynchronosShared/Migrations/20221024141548_GroupTempInvite.cs

@@ -1,5 +1,4 @@
-using System;
-using Microsoft.EntityFrameworkCore.Migrations;
+using Microsoft.EntityFrameworkCore.Migrations;
 
 #nullable disable
 

MareSynchronosServer/MareSynchronosShared/Models/GroupTempInvite.cs

@@ -1,9 +1,4 @@
-using System;
-using System.Collections.Generic;
-using System.ComponentModel.DataAnnotations;
-using System.Linq;
-using System.Text;
-using System.Threading.Tasks;
+using System.ComponentModel.DataAnnotations;
 
 namespace MareSynchronosShared.Models;