Register and tag releases 0.7.11 and 0.7.12

[cgarling]

#277 bumped the package version to 0.7.11 but as far as I can tell, that version was never officially registered. #286 bumped to 0.7.12 as it modified the compat entries in the Project.toml.

You could register both new versions, or you could revert the version on master back to 0.7.11 and just register that.

[timholy]

Thanks!

JuliaRegistries/General#136409
JuliaRegistries/General#136410