treewide: add license header and enable haslicense linter

Change-Id: I873a8d4082d75e8f813d8a726a41187eea7a065e
Reviewed-on: https://review.monogon.dev/c/monogon/+/3825
Tested-by: Jenkins CI
Reviewed-by: Leopold Schabel <leo@monogon.tech>
diff --git a/cloud/lib/component/component.go b/cloud/lib/component/component.go
index 1acd961..46fa58a 100644
--- a/cloud/lib/component/component.go
+++ b/cloud/lib/component/component.go
@@ -1,3 +1,6 @@
+// Copyright The Monogon Project Authors.
+// SPDX-License-Identifier: Apache-2.0
+
 // Package component implements reusable bits for cloud service components. Each
 // component is currently defined as being a standalone Go binary with its own
 // internal gRPC listener. Subsequent listeners (eg. public gRPC or HTTP) can be
diff --git a/cloud/lib/component/crdb.go b/cloud/lib/component/crdb.go
index 0bdbb4d..07306d1 100644
--- a/cloud/lib/component/crdb.go
+++ b/cloud/lib/component/crdb.go
@@ -1,3 +1,6 @@
+// Copyright The Monogon Project Authors.
+// SPDX-License-Identifier: Apache-2.0
+
 package component
 
 import (
diff --git a/cloud/lib/component/devcerts.go b/cloud/lib/component/devcerts.go
index 2a5f60a..837ad98 100644
--- a/cloud/lib/component/devcerts.go
+++ b/cloud/lib/component/devcerts.go
@@ -1,3 +1,6 @@
+// Copyright The Monogon Project Authors.
+// SPDX-License-Identifier: Apache-2.0
+
 package component
 
 import (