[CMake] Indicate NumPy dependency for tutorials that make use of it

[guitargeek]

This ensures that the tutorials that require NumPy are not run as unit tests if NumPy is not available in the environment.

[dpiparo]

Thanks. Should it be backported to 6.36 too perhaps?

[github-actions]

Test Results

    17 files      17 suites   3d 21h 52m 35s ⏱️
 2 730 tests  2 729 ✅ 0 💤 1 ❌
45 035 runs  45 034 ✅ 0 💤 1 ❌

For more details on these failures, see this check.

Results for commit 021ac0c.