feat: adding multi-arch support

Author: pacostas

.gitignore

@@ -2,3 +2,7 @@
 .idea/
 .DS_Store
 /build
+/bin
+/linux
+/darwin
+/windows

buildpack.toml

@@ -11,8 +11,18 @@ api = "0.7"
     uri = "https://github.com/paketo-buildpacks/yarn/blob/main/LICENSE"
 
 [metadata]
-  include-files = ["bin/run", "bin/build", "bin/detect", "buildpack.toml"]
-  pre-package = "./scripts/build.sh"
+  include-files = [
+    "buildpack.toml",
+    "linux/amd64/bin/build",
+    "linux/amd64/bin/detect",
+    "linux/amd64/bin/run",
+    "linux/arm64/bin/build",
+    "linux/arm64/bin/detect",
+    "linux/arm64/bin/run",
+  ]
+
+  pre-package = "./scripts/build.sh --target linux/amd64 --target linux/arm64"
+
   [metadata.default_versions]
     yarn = "1.*"
 
@@ -56,3 +66,11 @@ api = "0.7"
 
 [[stacks]]
   id = "*"
+
+[[targets]]
+  os = "linux"
+  arch = "amd64"
+
+[[targets]]
+  os = "linux"
+  arch = "arm64"