Upgrade Jest and drop Node 4

[rogeliog]

No description provided.

[ljharb]

Does this mean the runner will require jest 23?

[SimenB]

@ljharb yes, which is needed for #43

EDIT: I misspoke; this does not actually do that, it's just dev dep. And I suppose the plugin can work with whatever version of jest, but the watchplugins wouldn't work for consumers unless they upgrade.

However, we need the newest create-jest-runner for #43, and that requires Node 6. So it's a breaking change in that regard

[rogeliog]

@ljharb, it is just a devDepencency so it is just the version of Jest used to test this runner.

[rogeliog]

I guess it is fine to drop Node 4 now that its end of life has come https://github.com/nodejs/Release cc: @ljharb

[ljharb]

A node version being EOL means you could drop it; in no way does it mean one should.

However, jest’s aggressive dropping of node versions might force our hand, as a jest plugin.

[rogeliog]

@ljharb I agree 😄 ! As you mentioned, I meant this in the context of Jest already not supporting Node 4 jestjs/jest#4769