Recursive development dependency.

[davidlehn]

There is a development dependency on http-signature-zcap-verify. That package has a development dependency to this package. This should be addressed.

It looks as though both these packages are just each exporting a single main function: signCapabilityInvocation and verifyCapabilityInvocation. And tests for each package depend on the function from the other package. It looks as though these two packages should be merged into a single http-signature-zcap package. That would eliminate the dependency recursion. With modern tree shaking, package size issues should not be an issue, or perhaps will be improved.

Also see digitalbazaar/http-signature-zcap-verify#33.