fix: network time system tests should use double fixed delta time (#3373)

Adding the support to use a double delta time for
NetworkTimeSystemTests.

## Changelog

NA

## Testing and Documentation

- Includes update to the `NetworkTimeSystemTests.CorrectAmountTicksTest`
integration test.
- No documentation changes or additions were necessary.

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- [ ] An `[Obsolete]` attribute was added along with a `(RemovedAfter
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Author: NoelStephensUnity

com.unity.netcode.gameobjects/Runtime/Timing/NetworkTime.cs

@@ -50,6 +50,11 @@ public struct NetworkTime
         /// </summary>
         public float FixedDeltaTime => (float)m_TickInterval;
 
+        /// <summary>
+        /// Gets the fixed delta time as a double. This value is calculated by dividing 1.0 by the <see cref="TickRate"/> and stays constant.
+        /// </summary>
+        public double FixedDeltaTimeAsDouble => m_TickInterval;
+
         /// <summary>
         /// Gets the amount of network ticks which have passed until reaching the current time value.
         /// </summary>

com.unity.netcode.gameobjects/Tests/Runtime/Timing/NetworkTimeSystemTests.cs

@@ -62,35 +62,34 @@ public IEnumerator PlayerLoopTimeTest_WithDifferentTimeScale([Values(0.0f, 0.1f,
         public IEnumerator CorrectAmountTicksTest()
         {
             NetworkTickSystem tickSystem = NetworkManager.Singleton.NetworkTickSystem;
-            float delta = tickSystem.LocalTime.FixedDeltaTime;
+            double delta = tickSystem.LocalTime.FixedDeltaTimeAsDouble;
             int previous_localTickCalculated = 0;
             int previous_serverTickCalculated = 0;
 
             while (tickSystem.LocalTime.Time < 3f)
             {
                 yield return null;
 
-                var tickCalculated = tickSystem.LocalTime.Time / delta;
-                previous_localTickCalculated = (int)tickCalculated;
+                var localTickCalculated = tickSystem.LocalTime.Time / delta;
+                previous_localTickCalculated = (int)localTickCalculated;
 
                 // This check is needed due to double division imprecision of large numbers
-                if ((tickCalculated - previous_localTickCalculated) >= 0.999999999999)
+                if ((localTickCalculated - previous_localTickCalculated) >= 0.999999999999)
                 {
                     previous_localTickCalculated++;
                 }
 
-
-                tickCalculated = NetworkManager.Singleton.ServerTime.Time / delta;
-                previous_serverTickCalculated = (int)tickCalculated;
+                var serverTickCalculated = tickSystem.ServerTime.Time / delta;
+                previous_serverTickCalculated = (int)serverTickCalculated;
 
                 // This check is needed due to double division imprecision of large numbers
-                if ((tickCalculated - previous_serverTickCalculated) >= 0.999999999999)
+                if ((serverTickCalculated - previous_serverTickCalculated) >= 0.999999999999)
                 {
                     previous_serverTickCalculated++;
                 }
 
-                Assert.AreEqual(previous_localTickCalculated, NetworkManager.Singleton.LocalTime.Tick, $"Calculated local tick {previous_localTickCalculated} does not match local tick {NetworkManager.Singleton.LocalTime.Tick}!");
-                Assert.AreEqual(previous_serverTickCalculated, NetworkManager.Singleton.ServerTime.Tick, $"Calculated server tick {previous_serverTickCalculated} does not match server tick {NetworkManager.Singleton.ServerTime.Tick}!");
+                Assert.AreEqual(previous_localTickCalculated, NetworkManager.Singleton.LocalTime.Tick, $"Calculated local tick {previous_localTickCalculated} does not match local tick {NetworkManager.Singleton.LocalTime.Tick}!]n Local Tick-Calc: {localTickCalculated} LocalTime: {tickSystem.LocalTime.Time} | Server Tick-Calc: {serverTickCalculated} ServerTime: {tickSystem.ServerTime.Time} | TickDelta: {delta}");
+                Assert.AreEqual(previous_serverTickCalculated, NetworkManager.Singleton.ServerTime.Tick, $"Calculated server tick {previous_serverTickCalculated} does not match server tick {NetworkManager.Singleton.ServerTime.Tick}!\n Local Tick-Calc: {localTickCalculated} LocalTime: {tickSystem.LocalTime.Time} | Server Tick-Calc: {serverTickCalculated} ServerTime: {tickSystem.ServerTime.Time} | TickDelta: {delta}");
                 Assert.AreEqual((float)NetworkManager.Singleton.LocalTime.Time, (float)NetworkManager.Singleton.ServerTime.Time, $"Local time {(float)NetworkManager.Singleton.LocalTime.Time} is not approximately server time {(float)NetworkManager.Singleton.ServerTime.Time}!", FloatComparer.s_ComparerWithDefaultTolerance);
             }
         }