CI: update apt cache on Ubuntu before build

.github/workflows/ci.yml

@@ -51,6 +51,8 @@ jobs:
         crypto: [mbedtls, nettle, openssl]
     steps:
     - uses: actions/checkout@master
+    - name: Update apt cache
+      run: sudo apt-get update
     - name: Install dependencies
       run: sudo apt-get install -y autoconf automake build-essential cmake git libssl-dev nettle-dev libmbedtls-dev libacl1-dev libbz2-dev liblzma-dev liblz4-dev libzstd-dev lzop pkg-config zlib1g-dev
     - name: Autogen
@@ -87,6 +89,8 @@ jobs:
     runs-on: ubuntu-22.04
     steps:
     - uses: actions/checkout@master
+    - name: Update package definitions
+      run: sudo apt-get update
     - name: Install dependencies
       run: sudo apt-get install -y autoconf automake bsdmainutils build-essential cmake ghostscript git groff libssl-dev libacl1-dev libbz2-dev liblzma-dev liblz4-dev libzstd-dev lzop pkg-config zip zlib1g-dev
     - name: Autogen