Replace README.txt with README.md and update README.md file

The following error is observed when trying to apply patch:
1.patch:57: trailing whitespace.

warning: 1 line adds whitespace errors.

Please review.

Hi nitin_lama

I reviewed and applied MR!1 and confirmed that the README.txt was replaced with README.md and it is following the README.md template. Please see the screenshots attached.

Thank you.

Reviewed MR!1, the patch is working fine. Readme.md file is updated as per readme.md file template.

Reviewed MR!1, file is updated as per @apaderno comment and as per readme.md file template, "Navigate" is replaced with "Go to".
Hence marking it to RTBC.

Anjali Mehta → made their first commit to this issue’s fork.

@apaderno The file is updated as per your comment.
Definite article is added before the module name and line is updated to "The Content update from d7 module provides custom functionality to migrate the orders fields from Drupal 7 to Drupal 9."
As all the issues are fixed, marking it to RTBC.