Restore IE11 support

[ocean90]

This restores IE11 support which was accidentally broken since #50.

This updates the browserslist config for the browser version keeping the current config for the main/modern versions.

$ BROWSERSLIST_ENV=browser npx browserslist
and_chr 88
and_uc 12.12
chrome 88
chrome 87
edge 87
firefox 84
ie 11
ios_saf 14.0-14.4
ios_saf 13.4-13.7
op_mini all
safari 14
samsung 13.0

$ BROWSERSLIST_ENV=main npx browserslist
and_chr 88
and_uc 12.12
chrome 88
chrome 87
edge 87
firefox 84
ios_saf 14.0-14.4
ios_saf 13.4-13.7
op_mini all
safari 14
samsung 13.0

[midzer]

Looking good!

[midzer]

Thanks for your fast fix @ocean90