Install unzip in GH flow (now really)

Change-Id: I23e44156d0bb857bb75a32a404d6d8467b0ea90c
diff --git a/.github/workflows/linux.yml b/.github/workflows/linux.yml
index 3468d25..8f1e032 100644
--- a/.github/workflows/linux.yml
+++ b/.github/workflows/linux.yml
@@ -23,10 +23,10 @@
       - uses: actions/checkout@v2
       - name: perl -V
         run: perl -V
-      - name: apt install unzip
-        run: perl -V
+      - name: Install unzip
+        run: apt install unzip
       - name: Install dependencies
         run: |
-          cpanm --installdeps .
+          cpanm -n --installdeps .
       - name: Run tests
         run: prove -lr t/