Guides for Serilog and EFCore (#2134)

* Add serilog guide

* added suggestions from Rozen

* Add efcore guide

* Fix review changes

* Fix grammatical errors & review points

docs/guides/other_libs/samples/ModifyLogMethod.cs

@@ -0,0 +1,15 @@
+private static async Task LogAsync(LogMessage message)
+{
+    var severity = message.Severity switch
+    {
+        LogSeverity.Critical => LogEventLevel.Fatal,
+        LogSeverity.Error => LogEventLevel.Error,
+        LogSeverity.Warning => LogEventLevel.Warning,
+        LogSeverity.Info => LogEventLevel.Information,
+        LogSeverity.Verbose => LogEventLevel.Verbose,
+        LogSeverity.Debug => LogEventLevel.Debug,
+        _ => LogEventLevel.Information
+    };
+    Log.Write(severity, message.Exception, "[{Source}] {Message}", message.Source, message.Message);
+    await Task.CompletedTask;
+}