Map aarch64 to arm64 to fix docker issue on MacOS with Apple ARM chips (

#26)

fixes #18

src/Minifier/SystemUtils.php

@@ -64,7 +64,7 @@ private function getArchitecture(string $architecture): ?string
     {
         return match (\strtolower($architecture)) {
             'amd64', 'x86_64' => self::ARCH_AMD64,
-            'arm64' => self::ARCH_ARM64,
+            'aarch64', 'arm64' => self::ARCH_ARM64,
             'i386', 'i686' => self::ARCH_X86,
             default => null,
         };