Customer feedback | az webapp config | `--linux-fx-version` parameter needs more explanation

### Describe the bug

This GitHub issue is being moved from UUF [292301](https://dev.azure.com/msft-skilling/Content/_workitems/edit/292301).

### Summary
Please complete the following:
1. Update the `short-summary` for the `--linux-fx-version` parameter of the `az webapp config set` command.
2. Add more complex examples to `az webapp config set` command. There are 30 parameters and only 2 examples. Please see the [published reference guidelines](https://github.com/Azure/azure-cli/blob/dev/doc/reference_doc_guidelines.md#examples) for Azure CLI examples. For example, `Provide at least one example for every parameter. A single example can use multiple parameters, but a parameter that doesn't appear within an example code block often shows no usage statistics in Azure CLI reporting.`.

Link to [az webapp config set](https://learn.microsoft.com/en-us/cli/azure/webapp/config?view=azure-cli-latest)

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### Customer feedback from UUF
Repo:

azure-docs-cli

Title:
az webapp config | Microsoft Learn

Verbatim:
this is wrong? --linux-fx-versionThe runtime stack used for your linux-based webapp, e.g., "RUBY|2.5.5", "NODE|12LTS", "PHP|7.2", "DOTNETCORE|2.1". See https://aka.ms/linux-stacks for more info.should be with : for .NET Core , like--linux-fx-version "DOTNETCORE:8.0"not --linux-fx-version "DOTNETCORE|8.0"

Verbatim Id:
169f9854-da4f-ef11-a317-000d3a59d4e9

Triaged By:
v-ommikumar@microsoft.com

Triaged Comment:

Live URL:
https://learn.microsoft.com/en-us/cli/azure/webapp/config

GitHub URL:
https://github.com/MicrosoftDocs/azure-docs-cli/blob/live/2020-09-01-hybrid/docs-ref-autogen/webapp/config.yml

### Related command

az webapp config set

### Errors

n/a

### Issue script & Debug output

n/a

### Expected behavior

n/a

### Environment Summary

Based on the date of the UUF, I'm guessing Azure CLI 2.62.0

### Additional context

_No response_