Add Composer autoloading functions and PHPStan for testing

vendor/symfony/console/Tests/Fixtures/command_mbstring.md

@@ -0,0 +1,29 @@
+`descriptor:åèä`
+----------------
+
+command åèä description
+
+### Usage
+
+* `descriptor:åèä [-o|--option_åèä] [--] <argument_åèä>`
+* `descriptor:åèä -o|--option_name <argument_name>`
+* `descriptor:åèä <argument_name>`
+
+command åèä help
+
+### Arguments
+
+#### `argument_åèä`
+
+* Is required: yes
+* Is array: no
+* Default: `NULL`
+
+### Options
+
+#### `--option_åèä|-o`
+
+* Accept value: no
+* Is value required: no
+* Is multiple: no
+* Default: `false`