Add/update styling copyright header

src/nginxconfig/scss/_callout.scss

@@ -1,3 +1,29 @@
+/*
+Copyright 2021 DigitalOcean
+
+This code is licensed under the MIT License.
+You may obtain a copy of the License at
+https://github.com/digitalocean/nginxconfig.io/blob/master/LICENSE or https://mit-license.org/
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and / or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions :
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
 .callout {
   background: $callout;
   border-radius: $border-radius;

src/nginxconfig/scss/style.scss

@@ -1,5 +1,5 @@
 /*
-Copyright 2020 DigitalOcean
+Copyright 2021 DigitalOcean
 
 This code is licensed under the MIT License.
 You may obtain a copy of the License at