574 image not rendering in documentation

[cpaniaguam]

This pull request includes updates to the documentation and configuration for the IceFloeTracker project. The most important changes include updating the Documenter version, modifying the make.jl for compatibility with the new version, and improving the preprocessing documentation.

Preprocessing Documentation Improvements

• docs/src/preprocessing.md: Improved the preprocessing documentation by adding spaces, specifying the language for code blocks, and updating the image reference.

Documentation and Configuration Updates

• docs/Project.toml: Updated the Documenter dependency version from "0.27" to "1.8.1".

Documentation Generation Enhancements

• docs/make.jl: Enhanced the makedocs function by adding parameters for size_threshold, doctest, and warnonly to improve the documentation generation process.

[danielmwatkins]

Thanks for getting this together!