@apollo/client v4 support

[gregmartyn]

in @apollo/client v4, @apollo/client/link/core is now @apollo/client/link per
apollo-client-4-migration

As a result, the current version of generate-persisted-query-manifest errors with:

Error [ERR_PACKAGE_PATH_NOT_EXPORTED]: Package subpath './link/core' is not defined by "exports" in node_modules/@apollo/client/package.json

[bohlken34]

We’d love to see this issue prioritized — right now it’s blocking us from upgrading our production apps to Apollo Client v4. Happy to contribute a PR if it would help gain some traction.

[jerelmiller]

Sorry for the delay. I haven't watched this repo as closely.

@bohlken34 if you have some time to contribute, go for it! If not, I'll try to get to this sometime after GraphQL Summit (Oct 6-8).

[bohlken34]

Unfortunately I don't think I have as much time as I thought I did on my hands — I will probably not be able to contribute a PR after all.