{Doc} Update doc/try_new_features_before_release.md (#14990)

Co-authored-by: Feiyue Yu <iamyfy@163.com>

.github/CODEOWNERS

@@ -6,6 +6,7 @@
 
 /linter_exclusions.yml @MyronFanQiu @haroldrandom
 
+/doc/ @jiasli @qwordy @dbradish-microsoft
 /tools/ @haroldrandom @fengzhou-msft
 /scripts/ @haroldrandom @fengzhou-msft
 /src/azure-cli-testsdk/ @bim-msft @MyronFanQiu @haroldrandom

doc/try_new_features_before_release.md

@@ -1,5 +1,4 @@
-Try new features before release
-===
+# Try new features before release
 
 This documentation shows how to try new features in commit or PR before release even if the PR is not merged.
 
@@ -39,16 +38,18 @@ Follow the same steps in previous sessions and find artifact page. Click `pypi`
 
 ![](assets/6.PNG)
 
-```
+```powershell
 pip install azure_cli-2.6.0-py3-none-any.whl azure_cli_command_modules_nspkg-2.0.3-py3-none-any.whl azure_cli_core-2.6.0-py3-none-any.whl azure_cli_nspkg-3.0.4-py3-none-any.whl azure_cli_telemetry-1.0.4-py3-none-any.whl azure_mgmt_imagebuilder-1.0.0-py2.py3-none-any.whl
 ```
 `azure_cli-2.6.0-py3-none-any.whl`, `azure_cli_command_modules_nspkg-2.0.3-py3-none-any.whl`, `azure_cli_core-2.6.0-py3-none-any.whl`, `azure_cli_nspkg-3.0.4-py3-none-any.whl`, `azure_cli_telemetry-1.0.4-py3-none-any.whl` are packages of Azure CLI. `azure_mgmt_imagebuilder-1.0.0-py2.py3-none-any.whl` is a package of Image Builder resource provider. You should change it to your own SDK package containing the new feature.
 
-We recommend using a virtual environment to install the .whl files. This is an optional step.
+We recommend using a virtual environment to install the `.whl` files. This is an optional step.
 Example commands in PowerShell:
-```
+
+```powershell
 # Create a virtual environment 
 python -m venv env
+
 # Activate it
 env\Scripts\activate.ps1
 ```
@@ -57,19 +58,26 @@ env\Scripts\activate.ps1
 
 This approach is for geek users. You can test Azure CLI of any repository, any branch, any commit.
 
-```
+```powershell
 # You can also clone a fork of this repository
 git clone https://github.com/Azure/azure-cli.git
+
 # You can checkout any branch, any commit
-git checkout dev
-# Create a virtual environment
+git checkout <branch>/<commit>
+
+# Create a Python virtual environment
+# https://docs.python.org/3/using/cmdline.html#cmdoption-m
 python -m venv env
-# Activate it
+
+# Activate the virtual environment
 env\Scripts\activate.ps1
-# Install azdev
+
+# Install azdev - the development tool for Azure CLI
 pip install azdev
-# Install dependencies
+
+# Install dependencies. This may take about 5 minutes
 azdev setup -c azure-cli
+
 # Run Azure CLI
 az -v
 ```