ci: DK-5221 update python version to 3.13

Author: rackep

.github/workflows/pr-build.yaml

@@ -29,7 +29,7 @@ jobs:
 
       - uses: actions/setup-python@0b93645e9fea7318ecaed2b359559ac225c90a2b # v5.3.0
         with:
-          python-version: 3.7
+          python-version: 3.13
 
       - name: Set up chart-testing
         uses: helm/chart-testing-action@e6669bcd63d7cb57cb4380c33043eebe5d111992 # v2.6.1
@@ -201,7 +201,7 @@ jobs:
 
       - uses: actions/setup-python@0b93645e9fea7318ecaed2b359559ac225c90a2b # v5.3.0
         with:
-          python-version: 3.7
+          python-version: 3.13
 
       - name: Set up chart-testing
         uses: helm/chart-testing-action@e6669bcd63d7cb57cb4380c33043eebe5d111992 # v2.6.1