fix(deps): update module github.com/kcp-dev/kcp/sdk to v0.28.1 (#318)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

go.mod

@@ -22,7 +22,7 @@ require (
 	github.com/graphql-go/graphql v0.8.1
 	github.com/graphql-go/handler v0.2.4
 	github.com/hashicorp/go-multierror v1.1.1
-	github.com/kcp-dev/kcp/sdk v0.28.0
+	github.com/kcp-dev/kcp/sdk v0.28.1
 	github.com/kcp-dev/logicalcluster/v3 v3.0.5
 	github.com/openmfp/account-operator v0.170.24
 	github.com/openmfp/golang-commons v0.150.11

go.sum

@@ -105,8 +105,8 @@ github.com/kcp-dev/apimachinery/v2 v2.0.1-0.20250512171935-ebb573a40077 h1:lDi9n
 github.com/kcp-dev/apimachinery/v2 v2.0.1-0.20250512171935-ebb573a40077/go.mod h1:jnMZxVnCuKlkIXc4J1Qtmy1Lyo171CDF/RQhNAo0tvA=
 github.com/kcp-dev/controller-runtime v0.19.0-kcp.1.0.20250129100209-5eaf4c7b6056 h1:NaEaA34bHNawPL3npJN8J7jyQhA3eG+UQ0xZvTnOfYo=
 github.com/kcp-dev/controller-runtime v0.19.0-kcp.1.0.20250129100209-5eaf4c7b6056/go.mod h1:jwK5sBnpu/xJJ+xdpSzzI0aM52E/EvF0uLF9bR61h/Y=
-github.com/kcp-dev/kcp/sdk v0.28.0 h1:AOgGrgpqhrplbXMSbcvjFwCqwg4UlysTwIFZ0LvFxlk=
-github.com/kcp-dev/kcp/sdk v0.28.0/go.mod h1:8oZpWxkoMu2TDpx5DgdIGDigByKHKkeqVMA4GiWneoI=
+github.com/kcp-dev/kcp/sdk v0.28.1 h1:bTtuHVjFRjbwFEqXTPxc1J1JP2Hc3mTYqQ2xfJsi16M=
+github.com/kcp-dev/kcp/sdk v0.28.1/go.mod h1:8oZpWxkoMu2TDpx5DgdIGDigByKHKkeqVMA4GiWneoI=
 github.com/kcp-dev/logicalcluster/v3 v3.0.5 h1:JbYakokb+5Uinz09oTXomSUJVQsqfxEvU4RyHUYxHOU=
 github.com/kcp-dev/logicalcluster/v3 v3.0.5/go.mod h1:EWBUBxdr49fUB1cLMO4nOdBWmYifLbP1LfoL20KkXYY=
 github.com/kisielk/errcheck v1.5.0/go.mod h1:pFxgyoBC7bSaBwPgfKdkLd5X25qrDl4LWUI2bnpBCr8=