Add representative versions of Erlang/OTP 28 to CI (#325)

* Add representative versions of Erlang/OTP 28 to CI

* Update README and copyright year

Author: kostis

.github/workflows/ci.yml

@@ -20,6 +20,8 @@ jobs:
     strategy:
       matrix:
         otp:
+          - "28.3"
+          - "28.0"
           - "27.3"
           - "27.0"
           - "26.2"
@@ -46,7 +48,7 @@ jobs:
   examples:
     name: Test examples
     runs-on: ubuntu-latest
-    container: erlang:27.3
+    container: erlang:28.3
     steps:
       - name: Checkout code
         uses: actions/checkout@v6
@@ -56,7 +58,7 @@ jobs:
   parallel-examples:
     name: Test examples in parallel
     runs-on: ubuntu-latest
-    container: erlang:27.3
+    container: erlang:28.3
     steps:
       - name: Checkout code
         uses: actions/checkout@v6
@@ -66,7 +68,7 @@ jobs:
   coverage:
     name: Code coverage
     runs-on: ubuntu-latest
-    container: erlang:27.3
+    container: erlang:28.3
     steps:
       - name: Checkout code
         uses: actions/checkout@v6

README.md

@@ -26,7 +26,7 @@ You can reach PropEr's developers in the following ways:
 We welcome user contributions and feedback (comments, suggestions, feature
 requests, bug reports, patches, etc.).
 
-Copyright 2010-2025 by Manolis Papadakis, Eirini Arvaniti, and Kostis Sagonas.
+Copyright 2010-2026 by Manolis Papadakis, Eirini Arvaniti, and Kostis Sagonas.
 
 This program is distributed under the [GPL](http://www.gnu.org/licenses/gpl.html),
 version 3 or later. Please see the [COPYING][license] file for details.
@@ -195,7 +195,7 @@ incompatibilities between the two tools by now.
 <!-- Badges (alphabetically) -->
 [codecov badge]: https://codecov.io/gh/proper-testing/proper/branch/master/graph/badge.svg
 [commit badge]: https://img.shields.io/github/last-commit/proper-testing/proper.svg?style=flat-square
-[erlang versions badge]: https://img.shields.io/badge/erlang-21.3%20to%2027.3-blue.svg?style=flat-square
+[erlang versions badge]: https://img.shields.io/badge/erlang-21.3%20to%2028.3-blue.svg?style=flat-square
 [hex pm badge]: https://img.shields.io/hexpm/v/proper.svg?style=flat
 [license badge]: https://img.shields.io/github/license/proper-testing/proper.svg?style=flat-square
 [release badge]: https://img.shields.io/github/release/proper-testing/proper.svg?style=flat-square