[Helix] Don't fail fast on ef tool install issues (may be already installed)

[HaoK]

No description provided.

[HaoK]

Unrelated to this PR, so interesting @dougbu looks like the skip-ci only affects the aspnetcore-pr-validation-temp pipeline https://dev.azure.com/dnceng/public/_build?definitionId=279

[Pilchie]

Do we understand if this does the right thing if the wrong version of the ef tool is installed?

[davidfowl]

Seem like we should install or update.

[HaoK]

So my impression is that you can install multiple versions of the tool, and the failure we were running into was that the version we were trying to install was already installed (maybe the SDK caught up to our runtime version?)

[HaoK]

dotnet tool install dotnet-ef --global --version {Options.EfVersion} so we are specifying the exact version we want (the AspNetRuntime version)

[Pilchie]

We should verify that installing multiple versions actually works the way we expect. @wli3 - do you know about this?

[davidfowl]

Does it need to be installed globally? Seems like we should be installing it into a subfolder and using that instead no?

[BrennanConroy]

It should be installed in a local folder, I believe the DOTNET_CLI_HOME variable controls that. But it looks like we are no longer setting that after switching to the C# runner.

[HaoK]

Okay I can open a new PR on monday that switches to installing the tool non globally

[dougbu]

The bug here is not setting $env:DOTNET_CLI_HOME anymore. We should avoid global changes on the agents where possible because they are not recreated from an image after each use. Put another way, we set $env:DOTNET_CLI_HOME for reasons.

[davidfowl]

This should be part of the helix package #20876