diff --git a/.github/workflows/pull-request-management.yml b/.github/workflows/pull-request-management.yml
index e8fa04b7e..5b789a16f 100644
--- a/.github/workflows/pull-request-management.yml
+++ b/.github/workflows/pull-request-management.yml
@@ -95,7 +95,7 @@ jobs:
     strategy:
       fail-fast: true
       matrix:
-        python_version: [3.9,3.10,3.11,3.12]
+        python_version: ['3.9','3.10','3.11','3.12']
     steps:
       - name: 'set environment variables'
         run: |
@@ -120,7 +120,7 @@ jobs:
     strategy:
       fail-fast: true
       matrix:
-        python_version: [3.9,3.10,3.11,3.12]
+        python_version: ['3.9','3.10','3.11','3.12']
     steps:
       - name: 'set environment variables'
         run: |
@@ -253,7 +253,7 @@ jobs:
     strategy:
       fail-fast: true
       matrix:
-        python_version: [3.9,3.10,3.11,3.12]
+        python_version: ['3.9','3.10','3.11','3.12']
     steps:
       - name: 'set environment variables'
         run: |