VMR: remove FallbackPublicBaseURL from sdk.proj (#47505)

Author: akoeplinger

src/SourceBuild/content/repo-projects/sdk.proj

@@ -33,8 +33,6 @@
     <BuildArgs Condition="'$(TargetRid)' == 'linux-x64' or '$(TargetRid)' == 'linux-arm64' ">$(BuildArgs) /p:BuildSdkDeb=true /p:BuildSdkRpm=true</BuildArgs>
 
     <BuildArgs>$(BuildArgs) /p:PublicBaseURL=file:%2F%2F$(ArtifactsAssetsDir)</BuildArgs>
-    <!-- In non-source-only scenarios, currently consume aspnetcore from the normal public base url -->
-    <BuildArgs>$(BuildArgs) /p:FallbackPublicBaseURL=https://dotnetbuilds.blob.core.windows.net/public/</BuildArgs>
     <BuildArgs>$(BuildArgs) /p:UsePortableLinuxSharedFramework=false</BuildArgs>
 
     <BuildArgs Condition="'$(PgoInstrument)' == 'true'">$(BuildArgs) /p:PgoInstrument=true</BuildArgs>