docs: add new storage_download_byte_range samples

[BenWhitehead]

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[generated-files-bot]

Warning: This pull request is touching the following templated files:

• samples/snippets/pom.xml

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Here is the summary of changes.

You are about to add 1 region tag.

• samples/snippets/src/main/java/com/example/storage/object/DownloadByteRange.java:19, tag storage_download_byte_range

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[shaffeeullah]

Thanks, Ben!

[sydney-munro]

LGTM, looks like it does need a rebase though.