Binding credentials should include FIPS endpoints

[jameshochadel]

By default, the bind operation returns a non-FIPS GovCloud SES domain. SES supports FIPS endpoints and binding should return those endpoints instead.

• SES endpoint (scroll down in list for FIPS): https://docs.aws.amazon.com/general/latest/gr/ses.html
• FIPS Endpoints CLI instructions: https://docs.aws.amazon.com/general/latest/gr/rande.html#FIPS-endpoints

[jameshochadel]

Resolved in linked commit.