New packages Mvapich2x and Mvapich2-GDR (#17883)

* Adding new packages Mvapich2x and Mvapich2-GDR which can be installed only via binary mirrors

* Added docstring descriptions to both packages

* Removed variant wrapper for cuda dependencies

* Fixed multiple flake8 errors

* Updated APIs to pass unit tests

* Updated APIs for MVAPICH2-X package and fixed flake8 warnings for MVAPICH2-GDR

* Changed url back to single line

* Removed extra parantesis around URL string

Co-authored-by: nithintsk <nithintsk@github.com>