message: fix mac pkg installer path
diff: <key>GID</key>
  <integer>80</integer>
  <key>PATH</key>
  - <string>/Users/vishwas/Projects/symphony/SymphonyElectron/dist/mac/Symphony.app</string>
  + <string>../../dist/mac/Symphony.app</string>
  <key>PATH_TYPE</key>
  - <integer>0</integer>
  + <integer>3</integer>
  <key>PERMISSIONS</key>
  <integer>493</integer>
  <key>TYPE</key>
  