Update golang Docker tag to v1.25.4

Author: elastic-renovate-prod[bot]

.buildkite/pipeline.yml

@@ -7,14 +7,14 @@ steps:
   - label: ":go: lint"
     command: make lint
     agents:
-      image: "golang:1.25.1"
+      image: "golang:1.25.4"
       cpu: "4"
       memory: "8G"
 
   - label: ":go: tests"
     command: make unit-tests
     agents:
-      image: "golang:1.25.1"
+      image: "golang:1.25.4"
       cpu: "4"
       memory: "4G"