deps: update to latest

[jasonkuhrt]

closes #580

Basically we now say they should use TS 4.1. And in the future we'll force that without introducing a breaking change... I guess. 😕

It seems pedantic but we could apply a TS 4.1 feature somewhere just to force the upgrade and avoid confusion later. E.g.:

type Foobar = 'hello'
type ForceTS41 = `${Foobar} World`

[codecov]

Codecov Report

Merging #649 (8ceac6b) into develop (481e2c7) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff            @@
##           develop     #649   +/-   ##
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  Coverage    92.75%   92.75%           
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  Files           42       42           
  Lines         2732     2732           
  Branches       624      624           
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  Hits          2534     2534           
  Misses         195      195           
  Partials         3        3           

[jasonkuhrt]

Note https://github.com/microsoft/tslib/releases/tag/2.0.0

Requires TS 3.9+

But should be fine for us here since #580

[tgriesser]

Prettier needs to be bumped to 2.2 if you want to use any of the new template string features FYI, not that needs to happen here since we're not using any yet (and should probably hold off unless there's a compelling need).

[tgriesser]

Does tslib need to change to use 4.1?

[jasonkuhrt]

Does tslib need to change to use 4.1?

Not that I know of, but I figured we should update it as a matter of housekeeping.