feature #855 Updating composer deps, don't fail tests on vendor deprecations (bobdenotter)

This PR was squashed before being merged into the master branch (closes #855).

Discussion
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Updating composer deps, don't fail tests on vendor deprecations

Follows #846, replaces #854

I've taken the liberty of updating @nicolas-grekas' PR to update flex to 1.1, whilst keeping bound constraints for the symfony components.

Tests would fail on a deprecation in doctrine/common. I have also added a temporary `SYMFONY_DEPRECATIONS_HELPER=weak_vendors`, so it'll pass tests. After Symfony 4.2 has been released, I'll remove it.

Commits
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bbe1e49 Updating composer deps, don't fail tests on vendor deprecations

Author: javiereguiluz

bin/phpunit

@@ -14,5 +14,9 @@ if (false === getenv('SYMFONY_PHPUNIT_VERSION')) {
 if (false === getenv('SYMFONY_PHPUNIT_DIR')) {
     putenv('SYMFONY_PHPUNIT_DIR='.__DIR__.'/.phpunit');
 }
+if (false === getenv('SYMFONY_DEPRECATIONS_HELPER')) {
+    // see https://symfony.com/doc/current/components/phpunit_bridge.html#making-tests-fail
+    putenv('SYMFONY_DEPRECATIONS_HELPER=999999');
+}
 
 require dirname(__DIR__).'/vendor/symfony/phpunit-bridge/bin/simple-phpunit';

composer.json

@@ -15,7 +15,7 @@
         "sensiolabs/security-checker": "^4.1",
         "symfony/asset": "^4.1",
         "symfony/expression-language": "^4.1",
-        "symfony/flex": "^1.0.86",
+        "symfony/flex": "^1.1",
         "symfony/form": "^4.1",
         "symfony/framework-bundle": "^4.1",
         "symfony/monolog-bundle": "^3.1",
@@ -79,7 +79,8 @@
     },
     "extra": {
         "symfony": {
-            "allow-contrib": true
+            "allow-contrib": true,
+            "require": "4.1.*"
         }
     }
 }