docs: (PSKD-1500) update CONTRIBUTING.md with new expectations (#484)

* docs: (PSKD-1500) update CONTRIBUTING.md with new expectations

Signed-off-by: Ian Dominno <Ian.Dominno@sas.com>

* docs: (PSKD-1500) remove unnecessary bolds

* docs: (PSKD-1500) fix typo

Signed-off-by: Ian Dominno <Ian.Dominno@sas.com>

---------

Signed-off-by: Ian Dominno <Ian.Dominno@sas.com>

Author: iadomi

CONTRIBUTING.md

@@ -15,13 +15,54 @@ review. Our review process typically involves performing unit tests, development
 tests, integration tests, and security scans.
 
 ## Pull Request Requirement
-All contributions (PRs) must be accompanied by passing unit and/or integration
-tests, following our  [testing philosophy](./docs/user/TestingPhilosophy.md). If you are unfamiliar with this process,
-we are happy to help you navigate it by providing continuous collaboration within the pull request.
-All pull requests must also pass our linter analysis checks. Contributions might
-be subjected to security scans before they can be accepted.
+
+### Automated Tests
+All contributors are expected to include appropriate tests to ensure code quality
+and maintainability. This may include unit and/or integration tests as applicable
+to the scope of the changes.  We have a developed a Golang testing framework using
+[Terratest](https://terratest.gruntwork.io/) for unit tests and are in the process
+of developing integration tests. Please refer to our [Testing Philosopy](./docs/user/TestingPhilosophy.md)
+documentation for more information on our testing framework. If you need additional
+help and guidance, we are happy to help you navigate it by providing continuous
+collaboration within the pull request.
+
+### Conventional Commits
+All pull requests must follow the [Conventional Commit](https://www.conventionalcommits.org/en/v1.0.0/)
+standard for commit messages. This helps maintain a consistent and meaningful
+commit history. Pull requests with commits that do not follow the Conventional
+Commit format will not be merged.
+
+### Developer Certificate of Origin Sign-Off
+This project requires all commits to be signed off in accordance with the [Developer Certificate of Origin (DCO)](https://developercertificate.org/).
+By signing off your commits, you certify that you have the right to submit the
+contribution under the open source license used by this project.
+
+To sign off your commits, use the --signoff flag with git commit:
+
+```bash
+git commit --signoff -m "Your commit message"
+```
+
+This will add a Signed-off-by line to your commit message, e.g.:
+
+```bash
+Signed-off-by: You Name <your.email@example.com>
+```
+
+For more information, please refer to https://probot.github.io/apps/dco/
+
+### Linter Analysis Checks
+All pull requests must pass our automated analysis checks before they can be
+merged. These checks include:
+
+- **Hadolint** – for Dockerfile best practices
+- **ShellCheck** – for shell script issues
+- **TFLint** – for Terraform code quality
+- **Gitleaks** – for detecting hardcoded secrets and sensitive information
 
 ## Security Scans
-To ensure that all submissions meet our security and quality standards, we perform security
-scans using internal SAS infrastructure. Reporting of any Common Vulnerabilities and Exposures
-(CVEs) that are detected is not available in this project at this time.
+To ensure that all submissions meet our security and quality standards, we perform
+security scans using internal SAS infrastructure. Contributions might be subjected
+to security scans before they can be accepted. Reporting of any Common Vulnerabilities
+and Exposures (CVEs) that are detected is not available in this project at this
+time.