Prevent github.com/cloudflare/cfssl from being imported (#50089) (#50119

)

Updates the depguard rules to deny the dependency in favor of using
crypto or x/crypto and their subpackages instead.

.golangci.yml

@@ -76,6 +76,8 @@ linters-settings:
             desc: 'use "golang.org/x/mod/semver" or "coreos/go-semver/semver" instead'
           - pkg: github.com/microsoftgraph/msgraph-sdk-go
             desc: 'use "github.com/gravitational/teleport/lib/msgraph" instead'
+          - pkg: github.com/cloudflare/cfssl
+            desc: 'use "crypto" or "x/crypto" instead'
       # Prevent importing internal packages in client tools or packages containing
       # common interfaces consumed by them that are known to bloat binaries or break builds
       # because they only support a single platform.