When sending extended characters to the Md2HTML tool (using stdin and stdout) was replacing the characters by other weird symbols then for fixing this problem I'm encoding the info to base64 when sending and decoding the info when getting the html (from Md2HTML).

Moved methods DecodeHTMLContent and DecodeBase64 to the Md2HTML class (I had to convert the methods to be static).
Added comments in the EncodeBase64 method.
In the DecodeBase64 method the Catch section was updated

I've added a unit test that validates that the extended characters are processed correctly by the Md2Html.exe tool.
Also I've modified some methods in the Md2Html.cs file to be static

When running the test it was trying to read the files from a specific language location but that location doesn't exist when running the job so I copied the md file to a different location and modified the test to use this new location.

After debugging more and inserting logs inside the Md2Html.exe tool I notice that at the beginning when chosing the UTF-8 Encoding we were sending some weird characters so instead of using == now I'm using .Equals().
So I deleted the previous code for encoding and decoding the content and set to create the process with UTF-8.

Removing unnecessary usings.

Fixing test for parsing the html content with regular expressions