[COMPLIANCE] Add Copyright and License Headers (#2326)

Co-authored-by: hashicorp-copywrite[bot] <110428419+hashicorp-copywrite[bot]@users.noreply.github.com>
Co-authored-by: Carlos Alcaide Corvo <ccorvo@hashicorp.com>

ui/admin/app/components/form/field/list-wrapper/key-value/select.hbs

@@ -1,3 +1,8 @@
+{{!
+  Copyright (c) HashiCorp, Inc.
+  SPDX-License-Identifier: MPL-2.0
+}}
+
 <Hds::Form::Select::Base
   @value={{@value}}
   @width={{@width}}

ui/admin/app/components/form/field/list-wrapper/key-value/text.hbs

@@ -1,3 +1,8 @@
+{{!
+  Copyright (c) HashiCorp, Inc.
+  SPDX-License-Identifier: MPL-2.0
+}}
+
 <Hds::Form::TextInput::Field
   @value={{@value}}
   disabled={{@disabled}}