Use official repository for redis package.

.github/workflows/build.yml

@@ -14,7 +14,8 @@ jobs:
 
       - name: Install dependencies
         run: |
-          sudo add-apt-repository -y ppa:chris-lea/redis-server
+          curl -fsSL https://packages.redis.io/gpg | sudo gpg --dearmor -o /usr/share/keyrings/redis-archive-keyring.gpg
+          echo "deb [signed-by=/usr/share/keyrings/redis-archive-keyring.gpg] https://packages.redis.io/deb $(lsb_release -cs) main" | sudo tee /etc/apt/sources.list.d/redis.list
           sudo apt-get update
           sudo apt-get install -y redis-server valgrind libevent-dev