`README`: Missing link detailing supported annotation formats

There are multiple mentions to `annotations` both in the [README](https://github.com/iterative/ldb-resources#%CE%B1-readme) and the [Get started](https://github.com/iterative/ldb-resources/blob/main/documentation/Getting-started-with-LDB.md) (which appears to be misleading #5 ) but no direct link explaining what are the supported annotation formats.

The mentions of the supported annotations format I have found are in the [INDEX cmd ref]( https://github.com/iterative/ldb-resources/blob/main/documentation/Command-summary.md#index-storage-folder-uris--storage-object-uris--workspace-folder-flags ) and in the last section of [Get Started
](https://github.com/iterative/ldb-resources/blob/main/documentation/Getting-started-with-LDB.md#indexing-data-in-various-formats)

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Side note: The intro in the [INDEX cmd ref]( https://github.com/iterative/ldb-resources/blob/main/documentation/Command-summary.md#index-storage-folder-uris--storage-object-uris--workspace-folder-flags ) says:

> annotations in default format (one .json file per every data object sharing the object name)

However, according to the extended explanation of the flags, it seems that `strict-pairs, annotation-only, tensorflow-inferred` formats can all be detected by default.