Canonicalize provider version during default provider lookup

[EronWright]

Description

This PR addresses a problem that leads to two default providers for a given package+version. The problem occurs when given a combination of unversioned and versioned provider requests, as can occur in multi-language programs.

The fix is as follows: given an unversioned provider request, apply the default version before looking into the provider cache.

More background: #2767

Fixes #16108

Example

Given the example program from #16108 plus this fix, the stack state has one provider as expected:

{
    "urn": "urn:pulumi:dev::issue-1939-nodejs::pulumi:providers:kubernetes::default_4_10_0",
    "custom": true,
    "id": "c19b65b0-dd5a-432f-8c75-d7544de782ec",
    "type": "pulumi:providers:kubernetes",
    "inputs": {
        "version": "4.10.0"
    },
    "outputs": {
        "version": "4.10.0"
    },
    "created": "2024-05-02T21:22:09.72166Z",
    "modified": "2024-05-02T21:22:09.72166Z"
}
{
    "urn": "urn:pulumi:dev::issue-1939-nodejs::kubernetes:yaml/v2:ConfigGroup$kubernetes:core/v1:ConfigMap::example:eron/example",
    "custom": true,
    "id": "eron/example",
    "type": "kubernetes:core/v1:ConfigMap",
    "parent": "urn:pulumi:dev::issue-1939-nodejs::kubernetes:yaml/v2:ConfigGroup::example",
    "provider": "urn:pulumi:dev::issue-1939-nodejs::pulumi:providers:kubernetes::default_4_10_0::c19b65b0-dd5a-432f-8c75-d7544de782ec",
    "propertyDependencies": {
        "apiVersion": [],
        "kind": [],
        "metadata": []
    },
}

Checklist

• I have run make tidy to update any new dependencies
• I have run make lint to verify my code passes the lint check
  • I have formatted my code using gofumpt

• I have added tests that prove my fix is effective or that my feature works

• I have run make changelog and committed the changelog/pending/<file> documenting my change

• Yes, there are changes in this PR that warrants bumping the Pulumi Cloud API version

[pulumi-bot]

Changelog

[uncommitted] (2024-05-03)

Bug Fixes

• [engine] Normalize provider version during default provider lookup
  #16109

[EronWright]

I refactored the "normalization" logic out of newRegisterDefaultProviderEvent into a normalizeProviderRequest function, so that it could be executed before the provider cache is checked.

Note that the logic will execute more often, i.e. for cache hits and for misses, and so I simplified the logging a little bit.