Update some SqlProject integration dependencies

[ErikEJ]

Closes #918

PR Checklist

• Created a feature/dev branch in your fork (vs. submitting directly from a commit on main)
• Based off latest main branch of toolkit
• PR doesn't include merge commits (always rebase on top of our main, if needed)

Other information

[Copilot]

Pull Request Overview

This PR updates three core dependencies for the SQL Database Projects integration: Microsoft.SqlServer.DacFx, Microsoft.Build, and Microsoft.Build.Locator. The changes modernize the dependency versions while also correcting documentation to remove an outdated reference to ".sqlprojx" terminology.

• Updated Microsoft.SqlServer.DacFx from 170.1.61 to 170.2.70
• Updated Microsoft.Build from 17.11.31 to 17.14.28
• Updated Microsoft.Build.Locator from 1.9.1 to 1.10.2
• Corrected documentation to remove "(aka .sqlprojx)" reference

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
Directory.Packages.props	Updates three package versions for SqlProject dependencies
src/CommunityToolkit.Aspire.Hosting.SqlDatabaseProjects/README.md	Removes obsolete ".sqlprojx" terminology from documentation

[jmezach]

Could these types of updates be automated?

[ErikEJ]

@jmezach I will merge this when my previous PR is in 😄