spelling: github

Signed-off-by: Josh Soref <jsoref@users.noreply.github.com>

CONTRIBUTING.md

@@ -259,7 +259,7 @@ Like any good open source project, we use Pull Requests (PRs) to track code chan
       maintainers before it can be merged. Those with `size/XS` are per the judgement of the
       maintainers. For more detail see the [Size Labels](#size-labels) section.
 4. Reviewing/Discussion
-    - All reviews will be completed using Github review tool.
+    - All reviews will be completed using GitHub review tool.
     - A "Comment" review should be used when there are questions about the code that should be
       answered, but that don't involve code changes. This type of review does not count as approval.
     - A "Changes Requested" review indicates that changes to the code need to be made before they

README.md

@@ -54,7 +54,7 @@ Get started with the [Quick Start guide](https://helm.sh/docs/intro/quickstart/)
 
 ## Roadmap
 
-The [Helm roadmap uses Github milestones](https://github.com/helm/helm/milestones) to track the progress of the project.
+The [Helm roadmap uses GitHub milestones](https://github.com/helm/helm/milestones) to track the progress of the project.
 
 ## Community, discussion, contribution, and support