CI: Drop go1.25.x (#8675)

Author: beautifulentropy

.github/workflows/boulder-ci.yml

@@ -36,7 +36,6 @@ jobs:
       matrix:
         # Add additional docker image tags here and all tests will be run with the additional image.
         BOULDER_TOOLS_TAG:
-          - go1.25.8_2026-03-09
           - go1.26.1_2026-03-09
         # Tests command definitions. Use the entire "docker compose" command you want to run.
         tests:

.github/workflows/release.yml

@@ -35,7 +35,6 @@ jobs:
       fail-fast: false
       matrix:
         GO_VERSION:
-          - "1.25.8"
           - "1.26.1"
     runs-on: ubuntu-24.04
     permissions:

.github/workflows/try-release.yml

@@ -20,7 +20,6 @@ jobs:
       fail-fast: false
       matrix:
         GO_VERSION:
-          - "1.25.8"
           - "1.26.1"
     runs-on: ubuntu-24.04
     steps:

go.mod

@@ -1,6 +1,6 @@
 module github.com/letsencrypt/boulder
 
-go 1.25.0
+go 1.25
 
 require (
 	github.com/aws/aws-sdk-go-v2 v1.41.0

test/boulder-tools/tag_and_upload.sh

@@ -12,7 +12,7 @@ DOCKER_REPO="letsencrypt/boulder-tools"
 # .github/workflows/release.yml,
 # .github/workflows/try-release.yml if appropriate,
 # and .github/workflows/boulder-ci.yml with the new container tag.
-GO_CI_VERSIONS=( "1.25.8" "1.26.1" )
+GO_CI_VERSIONS=( "1.26.1" )
 
 echo "Please login to allow push to DockerHub"
 docker login