Fix valgrind installation on CI

Author: byroot

.github/workflows/ci.yaml

@@ -45,7 +45,7 @@ jobs:
         with:
           ruby-version: '3.1'
           bundler-cache: true # 'bundle install' and cache
-      - run: sudo apt-get install -y valgrind
+      - run: sudo apt-get update && sudo apt-get install -y valgrind
       - run: bundle exec rake spec:valgrind
 
   other: