Fix empty WebUI static assets directory

.github/workflows/build.yaml

@@ -23,7 +23,7 @@ jobs:
 
       - name: Build webui
         run: |
-          make generate-webui
+          make clean-webui generate-webui
           tar czvf webui.tar.gz ./webui/static/
 
       - name: Artifact webui

.github/workflows/test-unit.yaml

@@ -40,7 +40,7 @@ jobs:
           restore-keys: ${{ runner.os }}-test-unit-go-
 
       - name: Avoid generating webui
-        run: mkdir -p webui/static && touch webui/static/index.html
+        run: touch webui/static/index.html
 
       - name: Tests
         run: make test-unit

.github/workflows/validate.yaml

@@ -48,7 +48,7 @@ jobs:
         run: curl -sfL https://raw.githubusercontent.com/client9/misspell/master/install-misspell.sh | sh -s -- -b $(go env GOPATH)/bin ${MISSSPELL_VERSION}
 
       - name: Avoid generating webui
-        run: mkdir -p webui/static && touch webui/static/index.html
+        run: touch webui/static/index.html
 
       - name: Validate
         run: make validate