Extra bin-dir lookup feature

The Composer bin-dir path is usually changed by setting the composer config `bin-dir`, but another common way of doing it is, if the vendor directory itself is moved by changing the `vendor-dir` configuration.

src/Util/ComposerFile.php

@@ -29,6 +29,12 @@ public function getBinDir(): string
         if (null !== $binDir) {
             return (string) $binDir;
         }
+
+        $binDir = $this->configuration['config']['vendor-dir'] ?? null;
+
+        if (null !== $binDir) {
+            return (string) $binDir . '/bin';
+        }
 
         return 'vendor/bin';
     }