Update M.E.AI code coverage mins from 0

[stephentoub]

Based on #5640 (comment)

Microsoft Reviewers: Open in CodeFlow

[dotnet-comment-bot]

🎉 Good job! The coverage increased 🎉
Update MinCodeCoverage in the project files.

Project	Expected	Actual
Microsoft.Extensions.Diagnostics.Probes	70	76
Microsoft.Extensions.Caching.Hybrid	75	78
Microsoft.Extensions.AI.OpenAI	60	66
Microsoft.Extensions.AI.Ollama	75	80
Microsoft.Extensions.AI.Abstractions	80	83
Microsoft.Extensions.AI.AzureAIInference	70	77
Microsoft.Extensions.AI	80	83

Full code coverage report: https://dev.azure.com/dnceng-public/public/_build/results?buildId=880051&view=codecoverage-tab

[stephentoub]

We want the limits to be this tightly coupled to the current coverage? It breeds zero breathing room. Does the tooling fail CI if the coverage drops below the minimum?

[RussKie]

Does the tooling fail CI if the coverage drops below the minimum?

Yes

[RussKie]

This code coverage step was always there, it just the reporting of the issues to GitHub was failing due infra issues.

For example:

[dotnet-comment-bot]

🎉 Good job! The coverage increased 🎉
Update MinCodeCoverage in the project files.

Project	Expected	Actual
Microsoft.Extensions.Diagnostics.Probes	70	76
Microsoft.Extensions.Caching.Hybrid	75	84

Full code coverage report: https://dev.azure.com/dnceng-public/public/_build/results?buildId=880346&view=codecoverage-tab

[RussKie]

🎉 Good job! The coverage increased 🎉 Update MinCodeCoverage in the project files.

Project Expected Actual
Microsoft.Extensions.Diagnostics.Probes 70 76
Microsoft.Extensions.Caching.Hybrid 75 84
Full code coverage report: dev.azure.com/dnceng-public/public/_build/results?buildId=880346&view=codecoverage-tab

#5700 to address the remaining