Pulumitest disable automatic plugin acquisition by default

[VenelinMartinov]

What happened?

We should consider enabling PULUMI_DISABLE_AUTOMATIC_PLUGIN_ACQUISITION by default for the library as it is generally not useful for tests to install providers automatically - tests should either specify the versions of providers they want or use a local provider or explicitly opt-in to automatic plugin acquisition.

Additionally this also consumes GH API quotas which has caused flaky CI in the past.

Example

.

Output of pulumi about

.

Additional context

No response

Contributing

Vote on this issue by adding a 👍 reaction.
To contribute a fix for this issue, leave a comment (and link to your pull request, if you've opened one already).