chore: fix copyright headers (#1767)

Signed-off-by: Jan-Otto Kröpke <mail@jkroepke.de>

internal/collector/textfile/textfile.go

@@ -1,6 +1,4 @@
-//go:build windows
-
-// Copyright 2015 The Prometheus Authors
+// Copyright 2024 The Prometheus Authors
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
@@ -13,6 +11,8 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+//go:build windows
+
 package textfile
 
 import (