Change OpenACC configuration to match with math-support

What is the new feature

Improve OpenACC configuration

How is it implemented

This MR follows the configuration originally set up in the math-support library. See here for the reference.
This MR waits for !69 (merged) to be merged first.

Mandatory steps before review

• Gitlab CI passes (Hint: use make format for linting)
• New feature is covered by additional unit tests
• Mark the merge request as ready by removing Draft:

Mandatory steps before merge

• Test coverage does not decrease
• Reviewed by a maintainer
• Incorporate review suggestions
• Remember to edit the commit message and select the proper changelog category (feature/bugfix/other)

You are not supposed to merge this request by yourself, the maintainers of fortan-support take care of this action!