Add note about changes from Rusoto 0.24.0 to 0.25.0.
Add note about changes from Rusoto 0.24.0 to 0.25.0.

DualSpark/rust-aws,rusoto/rusoto,DualSpark/rusoto,rusoto/rusoto,DualSpark/rusoto,rusoto/rusoto,SecurityInsanity/rusoto,mattico/rusoto,SecurityInsanity/rusoto,DualSpark/rust-aws,DualSpark/rusoto,mattico/rusoto,DualSpark/rust-aws,mattico/rusoto