Prep 8.1.3

- up version and changelog
- tweak CI
- dart format

Merge pull request SpinlockLabs#266 from CaseyHillers/rate-limit-json…

…-fix

Fix getRateLimit json double casting ints

prep 8.1.1 release

Merge pull request SpinlockLabs#250 from CaseyHillers/rate-limit

Switch to dedicated rate_limit endpoint

improve pub score

Merge pull request SpinlockLabs#244 from SpinlockLabs/nullsafe

nullsafe migration

Merge pull request SpinlockLabs#249 from SpinlockLabs/nullsafe_2

Nullsafe 2

merged main

prep 7.0.4

Prep for 7.0.3