Retry apt-get install for memory-leaks config

This configuration is frequently failing due to HTTP 503 error
when installing valgrind. Retry the installation one time
after a short break to see if this would make the configuration
less flaky.

.github/workflows/test-memory-leaks.yaml

@@ -11,7 +11,7 @@ jobs:
           bundler-cache: true # runs 'bundle install' and caches installed gems automatically
           bundler: latest
           cache-version: v1 # bump this to invalidate cache
-      - run: sudo apt update && sudo apt install -y valgrind && valgrind --version
+      - run: sudo apt-get update && (sudo apt-get install -y valgrind || sleep 5 && sudo apt-get install -y valgrind) && valgrind --version
       - run: bundle exec rake compile spec:profiling:memcheck
   test-asan:
     # Temporarily disabled on 2024-09-17 until ruby-asan builds are available again on