docs(samples): Bulk insert sample

[m-strzelczyk]

Issue #278 shows that there needs to be some more documentation around Bulk Insert methods. This PR shows one basic example of how to use the bulk insert.

I know that the #278 is about per_instance_properties, but I wanted to start with something more basic.

[snippet-bot]

Here is the summary of changes.

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• samples/snippets/instances/bulk_insert.py:22, tag compute_instances_bulk_insert

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