fix(deps): update to graphql@15

[adriencohen]

Closes #298

[apollo-cla]

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[theprobugmaker]

bump

[barbieri]

bump

[dominicporter-MG]

I'm using graphql-tag with graphql 15.0.0 and it all seems to work (apart from the Peer Dep warning when you do npm i...

[airhorns]

It'd be great to get this in! It'd actually fix #298 . I think that issue is that specific user's issue where the typescript definitions aren't compatible between the two different versions of graphql-js included in his project. If we bumped the peer dependency of graphql-tag, the package manager could resolve graphql-js to the same version and actually make that issue go away!

I've been using graphql-tag with version 15 (just by forcing my package manager) and it has been working well for me. It'd be great to get this in.

[tunegov]

Merge it, please!

[hwillson]

Thanks @adriencohen!