bug #570 Fix Symfony 5 - dump-env (jderusse)

This PR was merged into the 1.4-dev branch.

Discussion
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Fix Symfony 5 - dump-env

Fixes #569

When using plugins, the composer autoloader use local project dependencies that match the plugin's `require`+`require-dev` dependencies.

Given flex plugin requires-dev `symfony/dotenv: ^3.4|^4.0`, composer's autoloader was not able to load the class Dotenv when in a project that requires `symfony/dotenv: ^5.0`.

Commits
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72c9a80 Fix Symfony 5 - dump-env

Author: fabpot

composer.json

@@ -15,9 +15,9 @@
     },
     "require-dev": {
         "composer/composer": "^1.0.2",
-        "symfony/dotenv": "^3.4|^4.0",
-        "symfony/phpunit-bridge": "^3.4.19|^4.1.8",
-        "symfony/process": "^2.7|^3.0|^4.0"
+        "symfony/dotenv": "^3.4|^4.0|^5.0",
+        "symfony/phpunit-bridge": "^3.4.19|^4.1.8|^5.0",
+        "symfony/process": "^2.7|^3.0|^4.0|^5.0"
     },
     "autoload": {
         "psr-4": {