fix(deps): update module github.com/alecthomas/kong to v1.15.0

| datasource | package                    | from    | to      |
| ---------- | -------------------------- | ------- | ------- |
| go         | github.com/alecthomas/kong | v1.14.0 | v1.15.0 |


Signed-off-by: renovate-sh-app[bot] <219655108+renovate-sh-app[bot]@users.noreply.github.com>

Author: renovate-sh-app[bot]

go.mod

@@ -3,7 +3,7 @@ module github.com/grafana/flux-commit-tracker
 go 1.25.7
 
 require (
-	github.com/alecthomas/kong v1.14.0
+	github.com/alecthomas/kong v1.15.0
 	github.com/fluxcd/kustomize-controller/api v1.8.2
 	github.com/fluxcd/source-controller/api v1.8.1
 	github.com/go-logr/logr v1.4.3

go.sum

@@ -2,8 +2,8 @@ github.com/Masterminds/semver/v3 v3.4.0 h1:Zog+i5UMtVoCU8oKka5P7i9q9HgrJeGzI9SA1
 github.com/Masterminds/semver/v3 v3.4.0/go.mod h1:4V+yj/TJE1HU9XfppCwVMZq3I84lprf4nC11bSS5beM=
 github.com/alecthomas/assert/v2 v2.11.0 h1:2Q9r3ki8+JYXvGsDyBXwH3LcJ+WK5D0gc5E8vS6K3D0=
 github.com/alecthomas/assert/v2 v2.11.0/go.mod h1:Bze95FyfUr7x34QZrjL+XP+0qgp/zg8yS+TtBj1WA3k=
-github.com/alecthomas/kong v1.14.0 h1:gFgEUZWu2ZmZ+UhyZ1bDhuutbKN1nTtJTwh19Wsn21s=
-github.com/alecthomas/kong v1.14.0/go.mod h1:wrlbXem1CWqUV5Vbmss5ISYhsVPkBb1Yo7YKJghju2I=
+github.com/alecthomas/kong v1.15.0 h1:BVJstKbpO73zKpmIu+m/aLRrNmWwxXPIGTNin9VmLVI=
+github.com/alecthomas/kong v1.15.0/go.mod h1:wrlbXem1CWqUV5Vbmss5ISYhsVPkBb1Yo7YKJghju2I=
 github.com/alecthomas/repr v0.5.2 h1:SU73FTI9D1P5UNtvseffFSGmdNci/O6RsqzeXJtP0Qs=
 github.com/alecthomas/repr v0.5.2/go.mod h1:Fr0507jx4eOXV7AlPV6AVZLYrLIuIeSOWtW57eE/O/4=
 github.com/beorn7/perks v1.0.1 h1:VlbKKnNfV8bJzeqoa4cOKqO6bYr3WgKZxO8Z16+hsOM=