chore: Move private packages to internal (#1664)

.promu.yml

@@ -2,6 +2,7 @@ go:
   # Whenever the Go version is updated here,
   # .github/workflows should also be updated.
   version: 1.23
+  cgo: false
 repository:
   path: github.com/prometheus-community/windows_exporter
 build:
@@ -21,4 +22,5 @@ tarball:
     - LICENSE
 crossbuild:
   platforms:
-    - windows
+    - windows/amd64
+    - windows/arm64