Bump oclif v4

[otaviojacobi]

In short: oclif v4 has been around for a few months already but because of oclif/oclif#1324 I have avoided bumping it (even though it has improvements and allows us to drop a patch).

However, now AWS SDK has fixed some of the dependency mess caused on downstream repos so that the issue above barely impacts us (in fact, it generates a smaller shrinkwrap 🎉 ) . This allows us to finally bump to oclif v4 and drop the last pending high vulnerability. Now down to 11 vulnerabilities, 10 coming from request library and 1 from got.

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