Move PurgeLuaScriptOnFinalize to Long-Running

It forces GC which can cause a pause...move it out of the normal test run.

StackExchange.Redis.Tests/Scripting.cs

@@ -746,7 +746,7 @@ private static void _PurgeLuaScriptOnFinalize(string script)
             Assert.Equal(1, LuaScript.GetCachedScriptCount());
         }
 
-        [Fact]
+        [FactLongRunning]
         public void PurgeLuaScriptOnFinalize()
         {
             const string Script = "redis.call('set', @PurgeLuaScriptOnFinalizeKey, @PurgeLuaScriptOnFinalizeValue)";