Use a human-readable date format for the `now` command's label (#13632)

Before:

![image](https://github.com/zed-industries/zed/assets/2690773/063887fb-1a28-4922-afd1-b2dc4117a03d)

After:
<img width="435" alt="Screenshot 2024-06-28 at 18 52 08"
src="https://github.com/zed-industries/zed/assets/2690773/8e9fd285-1991-4088-a93a-5ea3259d364a">
<img width="480" alt="Screenshot 2024-06-28 at 18 52 10"
src="https://github.com/zed-industries/zed/assets/2690773/7853fc90-6a63-4e66-bb83-2ed37d41b1b9">


Release Notes:

- N/A
7d767ff0a3Kirill Bulatov committed on 6/28/2024, 3:57:29 PM· committed by GitHubparent3cabd4b
1 file changedLine totals unavailable