Update dependency go to v1.25.4

Update go from 1.25.3 to 1.25.4

Change-type: patch

Author: balena-renovate[bot]

go.mod

@@ -2,7 +2,7 @@ module github.com/balena-io/sshproxy
 
 go 1.24.0
 
-toolchain go1.25.3
+toolchain go1.25.4
 
 require (
 	github.com/balena-io-modules/gexpect v0.0.0-20170619124017-ca1f0041f820