fix version number in the lesson

SarahAlidoost · SarahAlidoost · commit 3d5f2eeee719 · 2023-01-12T14:49:48.000+01:00
diff --git a/_episodes/08-diagnostics.md b/_episodes/08-diagnostics.md
@@ -2,7 +2,7 @@
 title: "Writing your own diagnostic script"
 teaching: 20
 exercises: 30
-compatibility: ESMValTool v2.4.0
+compatibility: ESMValTool v2.7.0
 
 questions:
 - "How do I write a new diagnostic in ESMValTool?"
