chore(deps): update go toolchain directive to v1.26.5

Author: renovate[bot]

go.mod

@@ -2,7 +2,7 @@ module github.com/OpenListTeam/OpenList/v4
 
 go 1.25.0
 
-toolchain go1.26.4
+toolchain go1.26.5
 
 require (
 	github.com/Azure/azure-sdk-for-go/sdk/azcore v1.18.1