explicitly set RDS cert to latest default for posterity

[davidsmejia]

Issue Number

#3505

Purpose/Implementation Notes

• Explicitly sets RDS CA identifier to rds-ca-rsa2048-g1

The current cert has expired and this one will be good through

I have manually updated this in the AWS console prior to deploying these changes. So that the next deploy will see that this change has already been applied and skip.

Types of changes

• Bugfix (non-breaking change which fixes an issue)

Functional tests

List out the functional tests you've completed to verify your changes work locally.

Checklist

Put an x in the boxes that apply.

• Lint and unit tests pass locally with my changes

Screenshots

N/A