Copy eng common fix

Author: Pavel Purma

eng/pipelines/dotnet-buildtools-prereqs-eng.yml

@@ -37,6 +37,6 @@ stages:
       linuxAmdBuildJobTimeout: 360
       linuxArmBuildJobTimeout: 300
       customPreImageBuilderBuildSteps:
-      - powershell: $(Build.SourcesDirectory)/dotnet-buildtools-prereqs-docker/eng/Stage-EngCommon.ps1
+      - powershell: $(Build.Repository.LocalPath)/eng/Stage-EngCommon.ps1
         displayName: Copy eng/common to build dirs
         condition: eq(variables['Agent.OS'], 'Linux')

eng/pipelines/dotnet-buildtools-prereqs-pr.yml

@@ -31,6 +31,6 @@ stages:
         demands: ImageOverride -equals build.ubuntu.2204.amd64.open
         os: linux
       customPreImageBuilderBuildSteps:
-      - powershell: $(Build.SourcesDirectory)/dotnet-buildtools-prereqs-docker/eng/Stage-EngCommon.ps1
+      - powershell: $(Build.Repository.LocalPath)/eng/Stage-EngCommon.ps1
         displayName: Copy eng/common to build dirs
         condition: eq(variables['Agent.OS'], 'Linux')

eng/pipelines/stages/dotnet-buildtools-prereqs.yml

@@ -25,7 +25,7 @@ stages:
         image: build.ubuntu.2204.amd64
         os: linux
       customPreImageBuilderBuildSteps:
-      - powershell: $(Build.SourcesDirectory)/eng/Stage-EngCommon.ps1
+      - powershell: $(Build.Repository.LocalPath)/eng/Stage-EngCommon.ps1
         displayName: Copy eng/common to build dirs
         condition: eq(variables['Agent.OS'], 'Linux')
       customBuildInitSteps: