Update module github.com/gruntwork-io/terratest to v0.40.8

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
github.com/gruntwork-io/terratest	require	patch	v0.40.7 -> v0.40.8

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Release Notes

gruntwork-io/terratest

### [`v0.40.8`](https://togithub.com/gruntwork-io/terratest/releases/v0.40.8) [Compare Source](https://togithub.com/gruntwork-io/terratest/compare/v0.40.7...v0.40.8) #### Modules affected - `slack` \[**NEW**] - `aws` #### Description - Fixed bug where `FunctionError` wasn't readable. - Added new module with utility functions for validating Slack integrations. #### Special thanks Special thanks to the following users for their contribution! - [@​m5lk3n](https://togithub.com/m5lk3n) - [@​raidancampbell](https://togithub.com/raidancampbell) #### Related links - [https://github.com/gruntwork-io/terratest/pull/1105](https://togithub.com/gruntwork-io/terratest/pull/1105) - [https://github.com/gruntwork-io/terratest/pull/1087](https://togithub.com/gruntwork-io/terratest/pull/1087) - [https://github.com/gruntwork-io/terratest/pull/1114](https://togithub.com/gruntwork-io/terratest/pull/1114)

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Configuration

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