Document jslib-aws v0.12.1

[oleiade]

What?

This Pull Request updates the jslib/aws documentation according to the changes made in v0.12.0 that we've just published.

Furthermore, I also went ahead and fixed the documentation and examples of the whole SignatureV4 API to address the recent undocumented changes we made to it.

Checklist

• [X] I have used a meaningful title for the PR.
• [X] I have described the changes I've made in the "What?" section above.
• [X] I have performed a self-review of my changes.
• [X] I have run the npm start command locally and verified that the changes look good.
• [X] I have made my changes in the docs/sources/next folder of the documentation.
• [X] I have reflected my changes in the docs/sources/v{most_recent_release} folder of the documentation.
• [X] I have reflected my changes in the relevant folders of the two previous k6 versions of the documentation (if still applicable to previous versions).

Related PR(s)/Issue(s)

https://github.com/grafana/k6-jslib-aws/releases/tag/v0.12.0

https://github.com/grafana/k6-jslib-aws/issues/102 https://github.com/grafana/k6-jslib-aws/issues/103 https://github.com/grafana/k6-jslib-aws/issues/67

[oleiade]

I've published jslib-aws v0.12.1 today, and updated the PR to reflect this change 👍🏻

[oleiade]

Up 👀 @heitortsergent, can I get your eyes on this, please? The current documentation is outdated 🙂