systems.md: Bring up-to-date with what was used at DAPC

Author: mpsijm

content/systems.md

@@ -75,17 +75,17 @@ The software configuration will consist of the following:
 The following languages are allowed during the contest:
 
 - C
-    - Compiler version: 13.2.0
+    - Compiler version: 13.3.0
     - Standard: gnu17
 - C++
-    - Compiler version: 13.2.0
+    - Compiler version: 13.3.0
     - Standard: gnu++20
 - Python
-    - Version: PyPy 7.3.17 (Python 3.10.14)
+    - Version: PyPy 7.3.19 (Python 3.11.11)
 - Java
-    - Version: 21.0.5
+    - Version: 21.0.6
 - Kotlin
-    - Version: 1.7.21
+    - Version: 2.1.20
 
 Note that Python 2 is no longer supported.
 
@@ -136,7 +136,7 @@ The following reference materials will be available on the teams' workstations t
 
 - [C reference from cppreference.com](https://en.cppreference.com/w/c)
 - [C++ reference from cppreference.com](https://en.cppreference.com/w/cpp)
-- [Python 3.10.13 documentation](https://docs.python.domainunion.de/release/3.10.13/)
-- [Java® Platform, Standard Edition & Java Development Kit Version 17 API Specification](https://docs.oracle.com/en/java/javase/17/docs/api/)
-- [Kotlin Language Documentation 1.6.20 (As PDF)](http://web.archive.org/web/20220610202819if_/https://kotlinlang.org/docs/kotlin-reference.pdf)
+- [Python 3.11.11 documentation](https://docs.python.org/release/3.11.11/)
+- [Java® Platform, Standard Edition & Java Development Kit Version 21 API Specification](https://docs.oracle.com/en/java/javase/21/docs/api/)
+- [Kotlin Language Documentation 2.1.20 (As PDF)](https://raw.githubusercontent.com/JetBrains/kotlin-web-site/e3ec93b63240397ae404e9c492b7dadaf2e67625/assets/kotlin-reference.pdf)
 - [DOMjudge Team Manual (As PDF)](https://www.domjudge.org/docs/manual/8.3/team.html)