Add CI test for --filter-ifname

Signed-off-by: Zhichuan Liang <gray.liang@isovalent.com>

Author: jschwinger233

.github/workflows/test.yml

@@ -114,7 +114,6 @@ jobs:
           expected-output-pattern: '1.1.1.1:80'
 
       - name: Test --filter-track-skb
-        # DNAT
         uses: ./.github/actions/pwru-test
         with:
           test-name: filter-track-skb
@@ -125,6 +124,16 @@ jobs:
             curl -vvv -sS --fail --connect-timeout "1" -o /dev/null http://10.10.20.99:80 || true
           expected-output-pattern: '10.10.14.2:80'
 
+      - name: Test --filter-ifname
+        uses: ./.github/actions/pwru-test
+        with:
+          test-name: filter-ifname
+          pwru-flags: --filter-ifname lo
+          pwru-pcap-filter: icmp
+          traffic-setup: |
+            ping -W1 -c1 127.0.0.1 || true
+          expected-output-pattern: 'icmp'
+
       - name: Fetch artifacts
         if: ${{ !success() }}
         uses: cilium/little-vm-helper@908ab1ff8a596a03cd5221a1f8602dc44c3f906d