[FIXUP] Add a missing apt-get update before dependencies installation.

Author: NlightNFotis

.github/workflows/pull-request-checks.yaml

@@ -71,6 +71,7 @@ jobs:
           # user input
           DEBIAN_FRONTEND: noninteractive
         run: |
+          sudo apt-get update
           sudo apt-get install --no-install-recommends -yq clang clang++ gdb maven jq flex bison libxml2-utils cpanminus
           make -C src minisat2-download
           cpanm Thread::Pool::Simple