golang:1.25.5

[mathieu-benoit]

golang:1.25.5 as base image of the builder target in Dockerfile to complete #3160 and fix CVEs.

While writing this blog post Security hardening of the OnlineBoutique sample apps with the Docker Hardened Images (DHI), I found out that the go.mod was updated recently there #3179 but not the Dockerfiles, fixing this here with this PR.

docker scout compare --ignore-unchanged --to checkout:1.25.4 checkout:1.25.5:

## Overview
  
                     │                    Analyzed Image                    │                   Comparison Image                   
  ───────────────────┼──────────────────────────────────────────────────────┼──────────────────────────────────────────────────────
   Target            │  checkout:1.25.5                                     │  checkout:1.25.4                                     
     digest          │  5daa71234709                                        │  5261dc954ae0                                        
     tag             │  1.25.5                                              │  1.25.4                                              
     platform        │ linux/amd64                                          │ linux/amd64                                          
     provenance      │ https://github.com/mathieu-benoit/microservices-demo │ https://github.com/mathieu-benoit/microservices-demo 
                     │  31577bd1219a375dbcf185ebed57778c92f2e4a6            │  31577bd1219a375dbcf185ebed57778c92f2e4a6            
     vulnerabilities │    0C     0H     0M     0L                           │    0C     1H     1M     0L                           
                     │           -1     -1                                  │                                                      
     size            │ 6.7 MB (+378 B)                                      │ 6.7 MB                                               
     packages        │ 58                                                   │ 58                                                   
                     │                                                      │

## Packages and Vulnerabilities
  
  
    ⎌    1 packages changed (↑ 1 upgraded, ↓ 0 downgraded)  
        54 packages unchanged
  
  
    - 2 vulnerabilities removed
  
  
     Package  Type    Version  Compared Version  
  
  ↑  stdlib   golang  1.25.5   1.25.4            
     ├─  -  HIGH         CVE-2025-61729  [https://scout.docker.com/v/CVE-2025-61729]  
     │                   7.5    
     └─  -  MEDIUM       CVE-2025-61727  [https://scout.docker.com/v/CVE-2025-61727]  
                         6.5

[mathieu-benoit]

Ready for your review, @bourgeoisor, thanks!

[bourgeoisor]

LGTM, thanks!