CI: Add yacc

Author: tony

.github/workflows/libtmux-ci.yml

@@ -22,7 +22,7 @@ jobs:
     - name: Build tmux ${{ matrix.tmux-version }}
       if: steps.tmux-build-cache.outputs.cache-hit != 'true'
       run: |
-        sudo apt install libevent-dev libncurses5-dev libtinfo-dev libutempter-dev
+        sudo apt install libevent-dev libncurses5-dev libtinfo-dev libutempter-dev bison
         mkdir ~/tmux-builds
         mkdir ~/tmux-src
         git clone https://github.com/tmux/tmux.git ~/tmux-src/tmux-${{ matrix.tmux-version }}