fix: bump oapi-codegen/runtime to v1.6.0 in testing module

The testing module uses pkg/api via a replace directive. After
pkg/api/go.mod was bumped to v1.6.0, testing/go.mod needs the
same indirect dependency update to keep the module graph consistent.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: ycombinator

testing/go.mod

@@ -60,7 +60,7 @@ require (
 	github.com/moby/sys/user v0.4.0 // indirect
 	github.com/moby/sys/userns v0.1.0 // indirect
 	github.com/moby/term v0.5.2 // indirect
-	github.com/oapi-codegen/runtime v1.5.0 // indirect
+	github.com/oapi-codegen/runtime v1.6.0 // indirect
 	github.com/opencontainers/go-digest v1.0.0 // indirect
 	github.com/opencontainers/image-spec v1.1.1 // indirect
 	github.com/pkg/errors v0.9.1 // indirect

testing/go.sum

@@ -117,8 +117,8 @@ github.com/moby/term v0.5.2 h1:6qk3FJAFDs6i/q3W/pQ97SX192qKfZgGjCQqfCJkgzQ=
 github.com/moby/term v0.5.2/go.mod h1:d3djjFCrjnB+fl8NJux+EJzu0msscUP+f8it8hPkFLc=
 github.com/oapi-codegen/nullable v1.1.0 h1:eAh8JVc5430VtYVnq00Hrbpag9PFRGWLjxR1/3KntMs=
 github.com/oapi-codegen/nullable v1.1.0/go.mod h1:KUZ3vUzkmEKY90ksAmit2+5juDIhIZhfDl+0PwOQlFY=
-github.com/oapi-codegen/runtime v1.5.0 h1:aiil4QnH+eiWYSO60eaYZ4aur7sJH3rz6BvT5EBFnxc=
-github.com/oapi-codegen/runtime v1.5.0/go.mod h1:GwV7hC2hviaMzj+ITfHVRESK5J2W/GefVwIND/bMGvU=
+github.com/oapi-codegen/runtime v1.6.0 h1:7Xx+GlueD6nRuyKoCPzL434Jfi3BetbiJOrzCHp/VPU=
+github.com/oapi-codegen/runtime v1.6.0/go.mod h1:GwV7hC2hviaMzj+ITfHVRESK5J2W/GefVwIND/bMGvU=
 github.com/opencontainers/go-digest v1.0.0 h1:apOUWs51W5PlhuyGyz9FCeeBIOUDA/6nW8Oi/yOhh5U=
 github.com/opencontainers/go-digest v1.0.0/go.mod h1:0JzlMkj0TRzQZfJkVvzbP0HBR3IKzErnv2BNG4W4MAM=
 github.com/opencontainers/image-spec v1.1.1 h1:y0fUlFfIZhPF1W537XOLg0/fcx6zcHCJwooC2xJA040=