Update metadata for ExperimentHub

[celsomilne]

Update data metadata to be consistent with feedback from ExperimentHub maintainer.

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• Please add some unique identifier to title and description. Currently I would not be able to tell what the difference is between the three files.
• Update the Bioc version to 3.12. This is the version the package will be released under once accepted.
• The RDataPath directory needs to start with the same name as the package. so scCyto should probably be scSpatial? And all three files have the same name. I assume there are three different files that need to be uploaded? The RDataPath should reflect the directory structure you plan to upload to S3. (e.g you would be uploading a folder scSpatial, with a subfolder Damond-Diabetes, with a subfolder 1.0, that has three files.