Update s3_configuration.md

[Avanividhani]

Added "." in documentation

Fixes #3584

Changes: added period in first step.

I have verified that this pull request:

• has no linting errors (npm run lint)
• has no test errors (npm run test)
• is from a uniquely-named feature branch and is up to date with the develop branch.
• is descriptively named and links to an issue number, i.e. Fixes #123

[welcome]

🎉 Thanks for opening this pull request! Please check out our contributing guidelines if you haven't already.

[raclim]

Thanks so much for catching this change, this is awesome! :)