chore(ci): update golangci-lint and fix script paths

- bump golangci-lint-action to v7 and version to v2.1.6
- correct directory paths in `smoke_test.sh`
- update `test` and `test-ci` targets in Makefile

.gitea/workflows/main.yml

@@ -46,6 +46,7 @@ jobs:
         uses: golangci/golangci-lint-action@v7
         with:
           version: v2.1.6
+          install-mode: goinstall
 
   test-linux:
     name: Test (Linux)
@@ -111,4 +112,4 @@ jobs:
         run: make build-ci
 
       - name: Run smoke tests
-        run: GREYWALL_TEST_NETWORK=1 ./scripts/smoke_test.sh ./greywall
+        run: ./scripts/smoke_test.sh ./greywall