Merge PR #4959 from @frack113 - Freeze pySigma to 0.11.9 before migra…

…tion to v2

chore: freeze pySigma before migrating all rules to v2

.github/workflows/sigma-test.yml

@@ -76,6 +76,7 @@ jobs:
     - name: Install dependencies
       run: |
         # pip install sigma-cli~=0.7.1
+        pip install pysigma==0.11.9
         pip install sigma-cli
         pip install pySigma-validators-sigmahq==0.7.0
     - name: Test Sigma Rule Syntax