fix(mac_shortcut.sh): fix `shellcheck` errors

```bash
In mysql/files/mac_shortcut.sh line 5:
if [[ -e "{{ home }}/{{ user }}/Desktop/{{ app }}" ]] && [[ "${1}" -eq "remove" ]]
                                                                       ^------^ SC2154: remove is referenced but not assigned.
In mysql/files/mac_shortcut.sh line 8:
elif [[ -e "{{ dir }}/{{ app ~ '.app' if suffix else app }}" ]] && [[ "${1}" -eq "add" ]]
                                                                                 ^---^ SC2154: add is referenced but not assigned.
```

mysql/files/mac_shortcut.sh

@@ -2,10 +2,10 @@
 
 CMD='/usr/bin/osascript -e'
 
-if [[ -e "{{ home }}/{{ user }}/Desktop/{{ app }}" ]] && [[ "${1}" -eq "remove" ]]
+if [[ -e "{{ home }}/{{ user }}/Desktop/{{ app }}" ]] && [[ "${1}" == "remove" ]]
 then
     $CMD "tell application \"Finder\" to delete POSIX file \"{{home}}/{{user}}/Desktop/{{ app }}\""
-elif [[ -e "{{ dir }}/{{ app ~ '.app' if suffix else app }}" ]] && [[ "${1}" -eq "add" ]]
+elif [[ -e "{{ dir }}/{{ app ~ '.app' if suffix else app }}" ]] && [[ "${1}" == "add" ]]
 then
     $CMD "tell application \"Finder\" to delete POSIX file \"{{home}}/{{user}}/Desktop/{{ app }}\"" >/dev/null 2>&1
     $CMD "tell application \"Finder\" to make new Alias at (path to desktop folder) to POSIX file \"{{ dir }}/{{ app }}{{ suffix or '' }}\""