Bump actions/setup-go from 5 to 6 (OpenAPITools#21902)

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]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

.github/workflows/samples-go-client-echo-api.yaml

@@ -17,7 +17,7 @@ jobs:
           - samples/client/echo_api/go
     steps:
       - uses: actions/checkout@v5
-      - uses: actions/setup-go@v5
+      - uses: actions/setup-go@v6
         with:
           go-version: "stable"
       - name: Setup node.js

.github/workflows/samples-go-client.yaml

@@ -19,7 +19,7 @@ jobs:
           - 'samples/openapi3/client/petstore/go/go-petstore-aws-signature/'
     steps:
       - uses: actions/checkout@v5
-      - uses: actions/setup-go@v5
+      - uses: actions/setup-go@v6
       - run: go version
       - name: Install Dependencies
         working-directory: ${{ matrix.sample }}

.github/workflows/samples-go-gin.yaml

@@ -22,7 +22,7 @@ jobs:
           - samples/server/petstore/go-gin-api-server-interface-only/
     steps:
       - uses: actions/checkout@v5
-      - uses: actions/setup-go@v5
+      - uses: actions/setup-go@v6
         with:
           go-version: "stable"
       - run: go version

.github/workflows/samples-go.yaml

@@ -28,7 +28,7 @@ jobs:
           - samples/server/others/go-server/no-body-path-params/
     steps:
       - uses: actions/checkout@v5
-      - uses: actions/setup-go@v5
+      - uses: actions/setup-go@v6
         with:
           go-version: "stable"
       - run: go version
@@ -49,7 +49,7 @@ jobs:
     steps:
       - uses: actions/checkout@v5
       - name: Set up Go
-        uses: actions/setup-go@v5
+        uses: actions/setup-go@v6
         with:
           go-version: ${{ matrix.go-version }}
       - name: Install Dependencies