Windows linux ico updates to c4 (#51)

* Updated multiple examples and validated updates

For examples\gcp-rhel-vm: Had to remove local versions.tf due to conflict of older version with root\version.tf thus just deleted the local versions.tf as it is not needed. After this was done - example VALIDATED.

For examples\gcp-windows-vm: Had to remove local versions.tf due to conflict of older version with root\version.tf thus just deleted the local versions.tf as it is not needed. After this was done - example VALIDATED.

For examples\gcp-windows-vm-ico-by-densify: variables.tf needed to be modified to set recommendedType = "c4-standard-4"- these changes were also don on readme.md, densify_recommendation.auto.tvars files - VALIDATED.

For examples\gcp-linux-vm-ico-by-densify: variables.tf needed to be modified to set recommendedType = "c4-standard-4"- these changes were also don on readme.md, densify_recommendation.auto.tvars files - VALIDATED.

* Updated all of the AI, TDX, and ICO modules and readme with update for C4

Updated all of the AI, TDX, and ICO modules and readme with update for C4

* Updated readme for RHEL

Author: daveshrestha-intel