switch schickling/mailcatcher to jeanberu/mailcatcher

[ivoba]

Q	A
License	MIT
Doc issue/PR	symfony/symfony-docs#...

Replace schickling/mailcatcher Docker image with jeanberu/mailcatcher because it is smaller with less MB.
Functionality should be the same.

schickling/mailcatcher: Compressed size: 25.44 MB
https://github.com/schickling/dockerfiles/blob/master/mailcatcher/Dockerfile

jeanberu/mailcatcher: Compressed size: 15.27 MB
https://github.com/Jean-Beru/docker-mailcatcher/blob/master/Dockerfile

This should save some MBs on the internets.

[github-actions]

Thanks for the PR 😍

How to test these changes in your application

1. Define the SYMFONY_ENDPOINT environment variable:

   # On Unix-like (BSD, Linux and macOS)
   export SYMFONY_ENDPOINT=https://raw.githubusercontent.com/symfony/recipes/flex/pull-1131/index.json
   # On Windows
   SET SYMFONY_ENDPOINT=https://raw.githubusercontent.com/symfony/recipes/flex/pull-1131/index.json

2. Install the package(s) related to this recipe:

   composer req 'symfony/flex:^1.16'
   composer req 'symfony/mailer:^4.3'

3. Don't forget to unset the SYMFONY_ENDPOINT environment variable when done:

   # On Unix-like (BSD, Linux and macOS)
   unset SYMFONY_ENDPOINT
   # On Windows
   SET SYMFONY_ENDPOINT=

Diff between recipe versions

In order to help with the review stage, I'm in charge of computing the diff between the various versions of patched recipes.
I'm going keep this comment up to date with any updates of the attached patch.

[fabpot]

Closing in favor of #1281