updated chef-cli version to 6.1.20 in stub

Signed-off-by: nikhil2611 <ngupta@progress.com>

Author: nikhil2611

.github/workflows/ci-main-pull-request-stub.yml

@@ -40,7 +40,7 @@ jobs:
       # go-private-modules: GOPRIVATE for Go private modules, default is 'github.com/progress-platform-services/*
 
       # if version specified, it takes precedence; can be a semver like 1.0.2-xyz or a tag like "latest"
-      version: '6.1.18' # ${{ github.event.repository.version }}
+      version: '6.1.20' # ${{ github.event.repository.version }}
       detect-version-source-type: 'none' # options include "none" (do not detect), "file", "github-tag" or "github-release"
       detect-version-source-parameter: '' # use for file name
       language: 'ruby'  # Go, Ruby, Rust, JavaScript, TypeScript, Python, Java, C#, PHP, other - used for build and SonarQube language setting