ci: use go version of go.mod

Author: rot1024

.github/workflows/ci-server.yml

@@ -1,7 +1,5 @@
 on:
   workflow_call:
-env:
-  GO_VERSION: "1.24"
 
 jobs:
   ci-server-lint:
@@ -13,7 +11,7 @@ jobs:
       - name: go setup
         uses: actions/setup-go@v5
         with:
-          go-version: ${{ env.GO_VERSION }}
+          go-version-file: server/go.mod
           cache-dependency-path: server/go.mod
       - name: golangci-lint
         uses: golangci/golangci-lint-action@v6
@@ -34,7 +32,7 @@ jobs:
       - name: go setup
         uses: actions/setup-go@v5
         with:
-          go-version: ${{ env.GO_VERSION }}
+          go-version-file: server/go.mod
           cache-dependency-path: server/go.mod
       - name: test
         run: go test ./... -v -race -coverprofile=coverage.txt -covermode=atomic -timeout 10m