EnhReq: Need ability to retrieve history of changes for Azure App Config keys

**Related command**

As of today - I could retrieve some configured entry and fields of names and last_modified in form like this:

`az appconfig feature show -n --key .appconfig.featureflag/ --fields name last_modified`

but I cannot find a way to retrieve history of changes, which I could see in Azure UI.

**Is your feature request related to a problem? Please describe.**

It's a problem of expected OOTB AZ CLI capabilities here.

**Describe the solution you'd like**

Not sure if `--history` option is used in some other AZ CLI commands. But potentially would like to be able to do like this:

`az appconfig feature show -n --key .appconfig.featureflag/ --fields name last_modified state --history`

**Describe alternatives you've considered**

The only known alternative so far is Azure Portal UI, which is inconvenient for better automation.

**Additional context**

N/A