CI: Stop installing cvc4 on archlinux

This change is in preparation for upgrading to cvc5. Since archlinux is
not running SMT tests anyway, we can drop cvc4 from the build
immediately.

.circleci/config.yml

@@ -1146,7 +1146,7 @@ jobs:
       - run:
           name: Install build dependencies
           command: |
-            pacman --noconfirm -Syu --noprogressbar --needed base-devel boost cmake cvc4 git openssh tar
+            pacman --noconfirm -Syu --noprogressbar --needed base-devel boost cmake git openssh tar
       - checkout
       - run_build
       - store_artifacts_solc
@@ -1273,7 +1273,7 @@ jobs:
       - run:
           name: Install runtime dependencies
           command: |
-            pacman --noconfirm -Syu --noprogressbar --needed base-devel boost cmake z3 cvc4 git openssh tar
+            pacman --noconfirm -Syu --noprogressbar --needed base-devel boost cmake z3 git openssh tar
       - soltest
 
   t_ubu_clang_soltest: &t_ubu_clang_soltest