[CI] CI on dev branch should use Knack's master branch

[jiasli]

CI on dev branch should use https://github.com/microsoft/knack master branch, instead of the public Knack on PyPI.

Otherwise, a compatibility issue with Knack can only be discovered after Knack is released to PyPI. To fix it, we will have to release Knack again, as shown in microsoft/knack#205 and microsoft/knack#206. This causes PyPI to contain un-usable Knack versions.

On the other hand, CI on release branch should use Knack on PyPI.

[yonzhan]

add to S170

[jiasli]

I think the same applies to azdev https://github.com/Azure/azure-cli-dev-tools. The CI should use the source code of azdev.

[yonzhan]

add to S172