ci: keep hidi at 1.6.24

Author: MIchaelMainer

.github/workflows/metadata-parser-validation.yml

@@ -36,7 +36,7 @@ jobs:
       with:
         dotnet-version: 9.x
 
-    - run: dotnet tool install --global Microsoft.OpenApi.Hidi
+    - run: dotnet tool install --global Microsoft.OpenApi.Hidi --version 1.6.24
       name: Install  Hidi
 
     - name: Validate latest XSLT rules