message: Fix broken GitHub links
diff: @@ -6,7 +6,7 @@ Thank you for your interest in contributing to Azure SDK for C++.
  - If you would like to become an active contributor to this project please follow the instructions provided in [Microsoft Azure Projects Contribution Guidelines](https://azure.github.io/azure-sdk/policies_opensource.html).
  -- To make code changes, or contribute something new, please follow the [GitHub Forks / Pull requests model](https://help.github.com/articles/fork-a-repo/): Fork the repo, make the change and propose it back by submitting a pull request.
  +- To make code changes, or contribute something new, please follow the [GitHub Forks / Pull requests model](https://docs.github.com/articles/fork-a-repo/): Fork the repo, make the change and propose it back by submitting a pull request.
  ## Pull Requests
  @@ -17,7 +17,7 @@ Thank you for your interest in contributing to Azure SDK for C++.
  - **DO NOT** submit "work in progress" PRs. A PR should only be submitted when it is considered ready for review and subsequent merging by the contributor.
  - If the change is work-in-progress or an experiment, **DO** start if off as a temporary draft PR.
  - **DO** give PRs short-but-descriptive names (e.g. "Improve code coverage for Azure.Core by 10%", not "Fix #1234") and add a description which explains why the change is being made.
  -- **DO** refer to any relevant issues, and include [keywords](https://help.github.com/articles/closing-issues-via-commit-messages/) that automatically close issues when the PR is merged.
  +- **DO** refer to any relevant issues, and include [keywords](https://docs.github.com/articles/closing-issues-via-commit-messages/) that automatically close issues when the PR is merged.
  - **DO** tag any users that should know about and/or review the change.
  - **DO** ensure each commit successfully builds. The entire PR must pass all tests in the Continuous Integration (CI) system before it'll be merged.
  - **DO** address PR feedback in an additional commit(s) rather than amending the existing commits, and only rebase/squash them when necessary. This makes it easier for reviewers to track changes.
  