Add toolchain built in includes to compiler switches

[LeFrosch]

Checklist

• [x] I have filed an issue about this change and discussed potential changes with the maintainers.
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Discussion thread for this change

Issue number: #6486

Description of this change

Add toolchain built in includes to compiler switches. Closes #6486.

[LeFrosch]

This might not be necessary after all. Because CLion can retrieve builtin includes from the compiler directly. Investigating why this was not working in my case.

[LeFrosch]

After further investigation I do not think this is necessary.