Bump symfony/process from 3.4.17 to 3.4.18

Bumps [symfony/process](https://github.com/symfony/process) from 3.4.17 to 3.4.18.
- [Release notes](https://github.com/symfony/process/releases)
- [Changelog](https://github.com/symfony/process/blob/master/CHANGELOG.md)
- [Commits](https://github.com/symfony/process/compare/v3.4.17...v3.4.18

)

Signed-off-by: dependabot[bot] <support@dependabot.com>

composer.lock

@@ -2384,16 +2384,16 @@
         },
         {
             "name": "symfony/process",
-            "version": "v3.4.17",
+            "version": "v3.4.18",
             "source": {
                 "type": "git",
                 "url": "https://github.com/symfony/process.git",
-                "reference": "1dc2977afa7d70f90f3fefbcd84152813558910e"
+                "reference": "35c2914a9f50519bd207164c353ae4d59182c2cb"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/symfony/process/zipball/1dc2977afa7d70f90f3fefbcd84152813558910e",
-                "reference": "1dc2977afa7d70f90f3fefbcd84152813558910e",
+                "url": "https://api.github.com/repos/symfony/process/zipball/35c2914a9f50519bd207164c353ae4d59182c2cb",
+                "reference": "35c2914a9f50519bd207164c353ae4d59182c2cb",
                 "shasum": ""
             },
             "require": {
@@ -2429,7 +2429,7 @@
             ],
             "description": "Symfony Process Component",
             "homepage": "https://symfony.com",
-            "time": "2018-10-02T12:28:39+00:00"
+            "time": "2018-10-14T17:33:21+00:00"
         },
         {
             "name": "theseer/tokenizer",