Revert "Fix Mono 4.8+"

This reverts commit a261dc44fd.

No longer needed, Mono switched to legacy TLS once again due to those issues.

ArchiSteamFarm/Runtime.cs

@@ -127,21 +127,6 @@ namespace ArchiSteamFarm {
 			}
 		}
 
-		// TODO: Remove me once BTLS in Mono 4.8+ is fixed
-		internal static bool RequiresNoCertificateValidation() {
-			if (!IsRunningOnMono) {
-				return false;
-			}
-
-			Version monoVersion = GetMonoVersion();
-
-			if (monoVersion?.Major != 4) {
-				return false;
-			}
-
-			return monoVersion.Minor >= 8;
-		}
-
 		private static Version GetNetVersion() {
 			uint release;
 			using (RegistryKey registryKey = RegistryKey.OpenBaseKey(RegistryHive.LocalMachine, RegistryView.Registry32).OpenSubKey("SOFTWARE\\Microsoft\\NET Framework Setup\\NDP\\v4\\Full\\")) {

ArchiSteamFarm/WebBrowser.cs

@@ -54,10 +54,6 @@ namespace ArchiSteamFarm {
 			// Don't use Expect100Continue, we're sure about our POSTs, save some TCP packets
 			ServicePointManager.Expect100Continue = false;
 
-			if (Runtime.RequiresNoCertificateValidation()) {
-				ServicePointManager.ServerCertificateValidationCallback += (s, ce, ca, p) => true;
-			}
-
 #if !__MonoCS__
 			// We run Windows-compiled ASF on both Windows and Mono. Normally we'd simply put code in the if
 			// However, if we did that, then we would still crash on Mono due to potentially calling non-existing methods