feat(Grist Node): Add support for self signed certificates on self hosted instances

[gregoo]

When testing on a local Grist instance with a self signed certificate, it can be useful to skip the validation.

A typical error with a self-signed certificate would look like this.

HTTP Code
UNABLE_TO_VERIFY_LEAF_SIGNATURE

Stack
NodeApiError: UNKNOWN ERROR - check the detailed error for more information
    at Object.gristApiRequest (/usr/local/lib/node_modules/n8n/node_modules/n8n-nodes-base/dist/nodes/Grist/GenericFunctions.js:32:15)
    at processTicksAndRejections (node:internal/process/task_queues:96:5)
    at async Object.execute (/usr/local/lib/node_modules/n8n/node_modules/n8n-nodes-base/dist/nodes/Grist/Grist.node.js:161:36)
    at async Workflow.runNode (/usr/local/lib/node_modules/n8n/node_modules/n8n-workflow/dist/Workflow.js:658:28)
    at async /usr/local/lib/node_modules/n8n/node_modules/n8n-core/dist/WorkflowExecute.js:585:53

This PR adds a Skip certificate validation toggle in the Grist credentials. It appears only if Self-Hosted is selected.

With that I'm able to validate my credentials and have my Grist node work.

(I'm no NodeJS expert, so, no clue how good the code is)

[CLAassistant]

All committers have signed the CLA.

[Joffcom]

Hey @gregoo,

Thanks for the PR, I have added a quick change which should allow the credentials to be used in the HTTP Request node as well, I don't have a local copy of Grist to hand if you get a chance could you give it a test just so I can make sure I have not broken anything.