Use podman only when docker binary is unavailable

Agent-Logs-Url: https://github.com/hykilpikonna/zshrc/sessions/f3bb0455-e68a-4be8-a7d5-b9fe6c79c7c4

Co-authored-by: hykilpikonna <22280294+hykilpikonna@users.noreply.github.com>

scripts/zshrc.sh

@@ -287,8 +287,8 @@ modern-replace 'tar' 'gtar'
 # for ArchLinux compat
 modern-replace 'code' 'visual-studio-code-electron'
 
-# If podman exists and docker doesn't exist, alias docker=podman
-if ! command -v docker &> /dev/null && command -v podman &> /dev/null; then
+# If podman binary exists and docker binary doesn't exist, alias docker=podman
+if (( ! $+commands[docker] && $+commands[podman] )); then
     alias docker='podman'
     if command -v podman-compose &> /dev/null; then
         alias docker-compose='podman-compose'