chore(deps): update dependency go to v1.26.0 (#711)

Co-authored-by: ske-renovate-ce[bot] <163154779+ske-renovate-ce[bot]@users.noreply.github.com>

Author: ske-renovate-ce[bot]

go.mod

@@ -2,7 +2,7 @@ module github.com/stackitcloud/cloud-provider-stackit
 
 go 1.24.6
 
-toolchain go1.25.7
+toolchain go1.26.0
 
 require (
 	github.com/container-storage-interface/spec v1.12.0