Update wgpu to v27

<!--Thank you for filing this! Please provide as much information as possible to help us diagnose and fix the issue--> ## Description Update wgpu to v27 Am willing to file PR including said version update, and fixes for examples if necessary. ## Repro steps <!--A runable example or short code sample showing how to reproduce the bug--> ## Extra Materials <!--Anything that could help us diagnose or fix the issue--> ## System Information <!--Version of imgui-wgpu-rs, information about your OS if relevant, your tech stack, etc.-->