- introduce new flag allowing to fetch reviewers who approved PRs

- add new testcase which verifies approvers being included
  - adjust config for some test cases to verify reviewers not being pulled if disabled

configs_test/configuration_approvers.json

@@ -0,0 +1,4 @@
+{
+    "template": "${{CHANGELOG}}",
+    "pr_template": "- ${{TITLE}} -- (#${{NUMBER}}) [${{STATUS}}] ${{REVIEWERS}} --- ${{APPROVERS}}"
+}