[AutoPR track2_azure-mgmt-network] Remove deprecated all-api-versions in readme.md

[openapi-sdkautomation]

Created to sync Azure/azure-rest-api-specs#10863.
(message created by the CI based on PR content)

Installation instruction

Package azure-mgmt-network

You can install the package azure-mgmt-network of this PR using the following command:
pip install "git+https://github.com/AzureSDKAutomation/azure-sdk-for-python@sdkAutomation/track2_azure-mgmt-network@10863#egg=azure-mgmt-network&subdirectory=azure-mgmt-network"

You can build a wheel to distribute for test using the following command:
pip wheel --no-deps "git+https://github.com/AzureSDKAutomation/azure-sdk-for-python@sdkAutomation/track2_azure-mgmt-network@10863#egg=azure-mgmt-network&subdirectory=azure-mgmt-network"

If you have a local clone of this repository, you can also do:

• git checkout sdkAutomation/track2_azure-mgmt-network@10863
• pip install -e ./azure-mgmt-network

Or build a wheel file to distribute for testing:

• git checkout sdkAutomation/track2_azure-mgmt-network@10863
• pip wheel --no-deps ./azure-mgmt-network

Direct download

Your files can be directly downloaded here:

• azure-mgmt-network-16.0.0.zip
• azure_mgmt_network-16.0.0-py2.py3-none-any.whl