ssh tunnel for postgres normalization

[Phlair]

What

Adds support for ssh tunnelling during normalization (& custom dbt transforms if non-Kube) for postgres destination.

Custom dbt transforms don't work on Kube as per this issue.

The core additions in this PR will enable other destinations to use ssh for normalization too provided ssh support/tests have been added as in Charles' PR. There is just a small update required per destination in airbyte-integrations/bases/base-normalization/normalization/transform_config/transform.py.

How

Added a bash script sshtunneling.sh that can read ssh tunnel options from the config file and if ssh tunneling is on, open an ssh tunnel using standard ssh procedure (and subsequently close it). Utilising a control-socket so we can target close the specific ssh session.

For key authorization, the key gets written to a tmp file and used in standard ssh command.

For password authorization, I've used sshpass to allow passing password non-interactively.

Notes

I'm aware that the implementation in airbyte-workers for custom dbt transforms is less than ideal. This is mainly due to the fact it runs on a user provided docker image rather than one we've defined. Specifically:

• Adding ssh script location to airbyte-workers gradle sourceSets to include in resources so we stay DRY.
• Requiring the user to ensure jq (and sshpass if using password auth) are installed on their provided docker image, albeit with a janky attempt to install these if they aren't present.
  This can definitely be improved (TODO: add link to issue for improving this here)
• Choosing our port to use in normalization transform.py and then writing this to a file in order to ensure we pick this up and use the same port in the sshtunneling script

New normalization will need to be published before the postgres tests can pass (I think)

Recommended reading order

1. sshtunneling.sh (core script for opening/closing ssh tunnel)
2. entrypoint.sh
3. dbt_transformation_entrypoint.sh
4. transform.py (normalization)
5. test_transform_config.py
6. everything else

Pre-merge Checklist

• Test/Publish base-normalization

[Phlair]

/test connector=bases/base-normalization

🕑 bases/base-normalization https://github.com/airbytehq/airbyte/actions/runs/1209981379
❌ bases/base-normalization https://github.com/airbytehq/airbyte/actions/runs/1209981379

[Phlair]

/test connector=bases/base-normalization

🕑 bases/base-normalization https://github.com/airbytehq/airbyte/actions/runs/1210540958
✅ bases/base-normalization https://github.com/airbytehq/airbyte/actions/runs/1210540958

[Phlair]

/test connector=bases/base-normalization

🕑 bases/base-normalization https://github.com/airbytehq/airbyte/actions/runs/1210663941
✅ bases/base-normalization https://github.com/airbytehq/airbyte/actions/runs/1210663941

[cgardens]

@Phlair - not sure what happened in this PR. I think merging in marcos branch broke the diff. Moved to a separate PR #5897 and cleaned it up and merged that into our base branch. Closing this now as it is duplicate.

[Phlair]

@cgardens good shout. You may have done this elsewhere but normalisation needs to be published first and then the postgres tests should work 👍