FRIDGE-1084 Change default concurrency limit

[victoray]

When multiple files are present in a project, you will get 429 as the toolkit spams API with requests and does not seem to do any sort of retries or uploading respecting endpoint rate limits. This is caused by the requests breaking the rate limits of some Twilio apis.

With this change the default concurrency limit is reduced, so avoid hitting rate limits.

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[changeset-bot]

🦋 Changeset detected

Latest commit: 319a405

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 2 packages

Name	Type
@twilio-labs/plugin-serverless	Patch
@twilio-labs/serverless-api	Patch

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