Remove deprecated function usage from gallery

[stefanv]

See, e.g., https://scikit-image.org/docs/stable/auto_examples/features_detection/plot_sift.html

[lagru]

Might be a good idea to setup the CI to fail on deprecation warnings raised by scikit-image (or deprecation warnings in general).

[mkcor]

@michaelbratsch is it okay if I assign this issue to you (cf. https://github.com/scikit-image/scikit-image/pull/7541#issuecomment-2351758494)? Thank you! :pray:

[github-actions[bot]]

Hello scikit-image core devs! There hasn't been any activity on this issue for more than 180 days. I have marked it as "dormant" to make it easy to find.

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