ci: bump actions/setup-go from 5 to 6

Bumps [actions/setup-go](https://github.com/actions/setup-go) from 5 to 6.
- [Release notes](https://github.com/actions/setup-go/releases)
- [Commits](actions/setup-go@v5...v6)

---
updated-dependencies:
- dependency-name: actions/setup-go
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

.github/workflows/ci-lint.yml

@@ -63,7 +63,7 @@ jobs:
         if: always() && github.actor != 'dependabot[bot]'
 
       - name: Set up Go
-        uses: actions/setup-go@v5
+        uses: actions/setup-go@v6
         with:
           go-version: "1.25.x"
         # Always run this step so that all linting errors can be seen at once.

.github/workflows/ci-test.yml

@@ -37,7 +37,7 @@ jobs:
         uses: actions/checkout@v5
 
       - name: Set up Go
-        uses: actions/setup-go@v5
+        uses: actions/setup-go@v6
         with:
           go-version: "1.25.x"
           cache: true
@@ -68,7 +68,7 @@ jobs:
         uses: actions/checkout@v5
 
       - name: Set up Go
-        uses: actions/setup-go@v5
+        uses: actions/setup-go@v6
         with:
           go-version: "1.25.x"
           cache: true

.github/workflows/release.yaml

@@ -19,7 +19,7 @@ jobs:
           fetch-depth: 0
 
       - name: Set up Go
-        uses: actions/setup-go@v5
+        uses: actions/setup-go@v6
         with:
           go-version: "1.25.x"