Consolidation for self contained, built on #34055 (#34134)

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fix/what does it change/how was it tested (even manually, if necessary)?
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## Summary of the Pull Request

First step on self containment. Once #34055 goes in, this number of
modified files should go way down.

Common.Selfcontained.props is the new item and
src/dsc/PowerToys.Settings.DSC.Schema.Generator/PowerToys.Settings.DSC.Schema.Generator.csproj
would be an example of a file that had SelfContained set to true prior
and now that logic was moved into a single file.

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## PR Checklist

- [ ] **Closes:** #xxx
- [ ] **Communication:** I've discussed this with core contributors
already. If work hasn't been agreed, this work might be rejected
- [ ] **Tests:** Added/updated and all pass
- [ ] **Localization:** All end user facing strings can be localized
- [ ] **Dev docs:** Added/updated
- [ ] **New binaries:** Added on the required places
- [ ] [JSON for
signing](https://github.com/microsoft/PowerToys/blob/main/.pipelines/ESRPSigning_core.json)
for new binaries
- [ ] [WXS for
installer](https://github.com/microsoft/PowerToys/blob/main/installer/PowerToysSetup/Product.wxs)
for new binaries and localization folder
- [ ] [YML for CI
pipeline](https://github.com/microsoft/PowerToys/blob/main/.pipelines/ci/templates/build-powertoys-steps.yml)
for new test projects
- [ ] [YML for signed
pipeline](https://github.com/microsoft/PowerToys/blob/main/.pipelines/release.yml)
- [ ] **Documentation updated:** If checked, please file a pull request
on [our docs
repo](https://github.com/MicrosoftDocs/windows-uwp/tree/docs/hub/powertoys)
and link it here: #xxx

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## Detailed Description of the Pull Request / Additional comments

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---------

Co-authored-by: Jaime Bernardo <jaime@janeasystems.com>

Directory.Build.props

@@ -85,7 +85,7 @@
     <UsePrecompiledHeaders Condition="'$(TF_BUILD)' != ''">false</UsePrecompiledHeaders>
 
     <!-- Change this to bust the cache -->
-    <MSBuildCacheCacheUniverse Condition="'$(MSBuildCacheCacheUniverse)' == ''">202407200737</MSBuildCacheCacheUniverse>
+    <MSBuildCacheCacheUniverse Condition="'$(MSBuildCacheCacheUniverse)' == ''">202408050737</MSBuildCacheCacheUniverse>
 
     <!--
       Visual Studio telemetry reads various ApplicationInsights.config files and other files after the project is finished, likely in a detached process.