[Feature Request]: Show checking for updates... before response from toDesktop

### Is there an existing issue for this?

- [x] I have searched the existing issues and checked the recent builds/commits

### What would your feature do ?

Before receiving a response from ToDesktop, change the Check For Updates button in the help menu to be grayed out and replace the text with something along the lines of Checking for updates.

### Proposed workflow

1. Click Check for updates
2. See its checking for updates

### Additional information

Very minor.

┆Issue is synchronized with this [Notion page](https://www.notion.so/Issue-3873-Feature-Request-Show-checking-for-updates-before-response-from-toDesktop-1f26d73d3650812ea4a8ef6244da9609) by [Unito](https://www.unito.io)