HarmBlockThreshold.BLOCK_NONE breaks embeddings creation

When running `python env_setup.py` (either v1 or v2), the flow stops due to the following error:

> google.api_core.exceptions.InvalidArgument: 400 User has requested a restricted HarmBlockThreshold setting BLOCK_NONE. You can get access either (a) through an allowlist via your Google account team, or (b) by switching your account type to monthly invoiced billing via this instruction: https://cloud.google.com/billing/docs/how-to/invoiced-billing.

This can be resolved by setting `HarmBlockThreshold.BLOCK_MEDIUM_AND_ABOVE` but should either be avoided or allow to be configured.

Thanks.