reformat error message string

[cpanato]

Description

reformat error message string to make a bit clear to the end user

Fixes #8057

Checklist

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

• I have updated the CHANGELOG-PENDING file with my change

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

[github-actions]

PR is now waiting for a maintainer to take action.

Note for the maintainer: Commands available:

• /run-acceptance-tests - used to test run the acceptance tests for the project
• /run-codegen - used to test the Pull Request against downstream codegen
• /run-docs-gen - used to test the Pull Request against documentation generation
• /run-containers - used to test the Pull Request against the containers tests

[cpanato]

/cc @lblackstone let me know if you want to update other places as well

[lblackstone]

Thanks for the PR, @cpanato!

It looks like the other messages should be ok as they are for now.