Docs: fix MSTest.Sdk badge URLs and typo in dev-guide

[Evangelink]

Small documentation fixes spotted while reviewing the repo entry points (README.md, CONTRIBUTING.md, docs/README.md, docs/dev-guide.md).

README.md

Fix MSTest.Sdk badge URLs

The MSTest.Sdk row in the package table used mstest.svg / mstest/vpre.svg for the stable/preview badges:

[![#](https://img.shields.io/nuget/v/mstest.svg?style=flat)](http://www.nuget.org/packages/MSTest.Sdk/)
[![#](https://img.shields.io/nuget/vpre/mstest.svg?style=flat)](http://www.nuget.org/packages/MSTest.Sdk/)

That made the badges show the version of the MSTest meta-package while linking to MSTest.Sdk — i.e. badge and link disagreed, and readers landing on the SDK row got the wrong version number. Now pointing the badge URLs at mstest.sdk.svg so they match the row's package (and the existing Azure Artifacts link).

Name consistency

MSTest, Microsoft Testing Framework, is a testing framework... — the same file's H1 is Microsoft Test Framework (MSTest). Replaced Testing -> Test to match.

docs/dev-guide.md

Typo (assets -> asserts)

The Debug/Release explanation said:

...the Release version...doesn't have any assets and has all code optimizations enabled.

The sentence is contrasting Release with the previous claim that Debug "includes asserts". Fixed the typo.

.Net -> .NET

In the VS workloads list, .Net Core cross-platform development — the two bullets above it already use .NET.

Build layout table missing TestResults

The artifacts/ directory tree lists TestResults but the legend table below doesn't describe it. Added a row.

docs/README.md

Writing your first test with mstest was the first bullet under "you can refer to the list of RFCs" — it's a learn.microsoft.com tutorial, not an RFC. Moved it into the "detailed examples" list above (where similar tutorial links live) and capitalized mstest -> MSTest.

Verification

No behavioral or build impact — Markdown-only doc changes.

[Copilot]

Pull request overview

This PR makes two small documentation corrections in the repo entry-point docs: it fixes the NuGet badge URLs for MSTest.Sdk in the main README so the displayed version matches the linked package, and corrects a typo in the dev guide’s Debug/Release explanation.

Changes:

• Update README.md so the MSTest.Sdk stable/preview Shields.io badge URLs point to mstest.sdk (instead of mstest).
• Fix a typo in docs/dev-guide.md (“assets” → “asserts”) in the Release build description.

Show a summary per file

File	Description
README.md	Corrects MSTest.Sdk NuGet badge URLs to match the package linked in the table row.
docs/dev-guide.md	Fixes a typo in the Debug vs Release build description (“assets” → “asserts”).

Copilot's findings

• Files reviewed: 2/2 changed files
• Comments generated: 0