ci: add missing dependency

Change-Id: I057f12e19c6ab841a1d62d4454329a654a7c38a5
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 2280aee..1ff7602 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -16,3 +16,5 @@
     uses: named-data/actions/.github/workflows/jenkins-script-macos.yml@v1
   PPA:
     uses: named-data/actions/.github/workflows/ppa.yml@v1
+    with:
+      extra-deps: libpsync-dev