Build agent docker image during CI (#725)

.github/workflows/pr_validation.yml

@@ -12,7 +12,7 @@ concurrency:
 
 jobs:
   build-cli:
-    name: Build CLI
+    name: Build CLI executable
     runs-on: ubuntu-latest
     steps:
       - name: Set up Go 1.16
@@ -27,35 +27,11 @@ jobs:
         run: make cli
 
   build-agent:
-    name: Build Agent
+    name: Build Agent docker image
     runs-on: ubuntu-latest
     steps:
-      - name: Set up Go 1.16
-        uses: actions/setup-go@v2
-        with:
-          go-version: '1.16'
-
       - name: Check out code into the Go module directory
         uses: actions/checkout@v2
 
-      - shell: bash
-        run: |
-          sudo apt-get install libpcap-dev
-
       - name: Build Agent
-        run: make agent
-
-  build-ui:
-    name: Build UI
-    runs-on: ubuntu-latest
-    steps:
-      - name: Set up Node 16
-        uses: actions/setup-node@v2
-        with:
-          node-version: '16'
-
-      - name: Check out code into the Go module directory
-        uses: actions/checkout@v2
-
-      - name: Build UI
-        run: make ui
+        run: make agent-docker