fix: simplify CI to use only Go 1.21

- Remove unnecessary Go 1.22 from build matrix
- Match go.mod requirement of Go 1.21
- Reduce CI build time by half

Author: ktcadmium

.github/workflows/ci.yml

@@ -48,7 +48,6 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu-latest, macos-latest]
-        go: ['1.21', '1.22']
     runs-on: ${{ matrix.os }}
 
     steps:
@@ -63,13 +62,13 @@ jobs:
     - name: Set up Go
       uses: actions/setup-go@v5
       with:
-        go-version: ${{ matrix.go }}
+        go-version: '1.21'
 
     - name: Build
       run: go build -v -o kubectl-rebalance ./cmd/kubectl-rebalance
 
     - name: Upload artifact
       uses: actions/upload-artifact@v4
       with:
-        name: kubectl-rebalance-${{ matrix.os }}-go${{ matrix.go }}
+        name: kubectl-rebalance-${{ matrix.os }}
         path: kubectl-rebalance