Update go version within go.mod

[nlacey]

Currently you have go version set to 1.16 within your go.mod file.

The problem with this is you are missing the new (indirect) deps added to the go.mod file.
Which makes it easier to see indirect security problems

EA update go 1.16 to go 1.17 would give you

module github.com/lestrrat-go/jwx/v2

go 1.17

require (
github.com/decred/dcrd/dcrec/secp256k1/v4 v4.2.0
github.com/goccy/go-json v0.10.2
github.com/lestrrat-go/blackmagic v1.0.2
github.com/lestrrat-go/httprc v1.0.4
github.com/lestrrat-go/iter v1.0.2
github.com/lestrrat-go/option v1.0.1
github.com/segmentio/asm v1.2.0
github.com/stretchr/testify v1.8.4
golang.org/x/crypto v0.16.0
)

require (
github.com/davecgh/go-spew v1.1.1 // indirect
github.com/lestrrat-go/httpcc v1.0.1 // indirect
github.com/pmezard/go-difflib v1.0.0 // indirect
golang.org/x/sys v0.15.0 // indirect
gopkg.in/yaml.v3 v3.0.1 // indirect
)