Update README.md

Note about OS certificates and proxies not being supported yet

README.md

@@ -55,6 +55,8 @@ Unfortunately, at this time we are not able to support the extension with [remot
 We have enabled experimental functionality to support GitHub Enterprise Server, but this feature is an experimental beta and currently unsupported. To try this out, enable the `use-enterprise` setting to authenticate with your `GitHub Enterprise Server Authentication Provider` settings
 <img width="975" alt="Use-enterprise setting checkbox" src="https://github.com/github/vscode-github-actions/assets/34719884/be76adc6-64af-47ed-84d0-627786cc4eea">
 
+We currently do not have the capability to support OS certificates or enterprise proxies, but we have plans for it in the future and it is on our backlog!
+
 ## Contributing
 
 See [CONTRIBUTING.md](CONTRIBUTING.md). A description of the architecture of the extension can be found [here](./docs/project-architecture.md).