Remove primary constructor syntax

The primary constructor syntax seems to be not supported by older dotnet
versions, so don't use it. Also switch from `class` to `struct`, to
better reflect the fact that RedisValueWithScore is just a data storage
item.

Author: Gabriel Erzse

src/NRedisStack/CoreCommands/DataTypes/RedisValueWithScore.cs

@@ -3,20 +3,29 @@
 namespace NRedisStack.Core.DataTypes;
 
 /// <summary>
-/// Holds a value with an associated score.
+/// Holds a <see cref="RedisValue"/> with an associated score.
 /// Used when working with sorted sets.
 /// </summary>
-public class RedisValueWithScore(RedisValue value, double score)
+public struct RedisValueWithScore
 {
+    /// <summary>
+    /// Pair a <see cref="RedisValue"/> with a numeric score.
+    /// </summary>
+    public RedisValueWithScore(RedisValue value, double score)
+    {
+        Value = value;
+        Score = score;
+    }
+
     /// <summary>
     /// The value of an item stored in a sorted set. For example, in the Redis command
     /// <c>ZADD my-set 5.1 my-value</c>, the value is <c>my-value</c>.
     /// </summary>
-    public RedisValue Value { get; } = value;
+    public RedisValue Value { get; }
 
     /// <summary>
     /// The score of an item stored in a sorted set. For example, in the Redis command
     /// <c>ZADD my-set 5.1 my-value</c>, the score is <c>5.1</c>.
     /// </summary>
-    public double Score { get; } = score;
+    public double Score { get; }
 }