Simplify constant TimeSpan retrieval

`TimeSpan.Parse` may behave differently depending on culture settings.

Author: xtqqczze

src/libraries/System.Transactions.Local/src/System/Transactions/Configuration/ConfigurationStrings.cs

@@ -6,7 +6,5 @@ namespace System.Transactions.Configuration
     internal static class ConfigurationStrings
     {
         internal const string DefaultDistributedTransactionManagerName = "";
-        internal const string DefaultMaxTimeout = "00:10:00";
-        internal const string DefaultTimeout = "00:01:00";
     }
 }

src/libraries/System.Transactions.Local/src/System/Transactions/Configuration/DefaultSettingsSection.cs

@@ -6,12 +6,11 @@ namespace System.Transactions.Configuration
     internal sealed class DefaultSettingsSection // ConfigurationSection
     {
         private static readonly DefaultSettingsSection s_section = new DefaultSettingsSection();
-        private static readonly TimeSpan s_timeout = TimeSpan.Parse(ConfigurationStrings.DefaultTimeout);
 
         internal static DefaultSettingsSection GetSection() => s_section;
 
         public static string DistributedTransactionManagerName { get; set; } = ConfigurationStrings.DefaultDistributedTransactionManagerName;
 
-        public static TimeSpan Timeout => s_timeout;
+        public static TimeSpan Timeout => TimeSpan.FromMinutes(1);
     }
 }

src/libraries/System.Transactions.Local/src/System/Transactions/Configuration/MachineSettingsSection.cs

@@ -6,10 +6,9 @@ namespace System.Transactions.Configuration
     internal sealed class MachineSettingsSection // ConfigurationSection
     {
         private static readonly MachineSettingsSection s_section = new MachineSettingsSection();
-        private static readonly TimeSpan s_maxTimeout = TimeSpan.Parse(ConfigurationStrings.DefaultMaxTimeout);
 
         internal static MachineSettingsSection GetSection() => s_section;
 
-        public static TimeSpan MaxTimeout => s_maxTimeout;
+        public static TimeSpan MaxTimeout => TimeSpan.FromMinutes(10);
     }
 }