build(deps): bump github.com/oapi-codegen/runtime in /pkg/api

Bumps [github.com/oapi-codegen/runtime](https://github.com/oapi-codegen/runtime) from 1.5.0 to 1.6.0.
- [Release notes](https://github.com/oapi-codegen/runtime/releases)
- [Commits](oapi-codegen/runtime@v1.5.0...v1.6.0)

---
updated-dependencies:
- dependency-name: github.com/oapi-codegen/runtime
  dependency-version: 1.6.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

pkg/api/go.mod

@@ -2,7 +2,7 @@ module github.com/elastic/fleet-server/pkg/api
 
 go 1.25.0
 
-require github.com/oapi-codegen/runtime v1.5.0
+require github.com/oapi-codegen/runtime v1.6.0
 
 require (
 	github.com/apapsch/go-jsonmerge/v2 v2.0.0 // indirect

pkg/api/go.sum

@@ -10,8 +10,8 @@ github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+
 github.com/juju/gnuflag v0.0.0-20171113085948-2ce1bb71843d/go.mod h1:2PavIy+JPciBPrBUjwbNvtwB6RQlve+hkpll6QSNmOE=
 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/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/spkg/bom v0.0.0-20160624110644-59b7046e48ad/go.mod h1:qLr4V1qq6nMqFKkMo8ZTx3f+BZEkzsRUY10Xsm2mwU0=