Merge in 'release/2.1.5xx' changes

Author: dotnet-bot

.vsts-ci.yml

@@ -27,24 +27,6 @@ jobs:
       testResultsFiles: '**/*.trx'
     condition: always()
 
-- job: debug_debian82_x64
-  displayName: Debian8.2 x64 Debug Build
-  pool:
-    ${{ if eq(variables['System.TeamProject'], 'public') }}:
-      name: NetCorePublic-Pool
-      queue: BuildPool.Ubuntu.1604.Amd64.Open
-    ${{ if eq(variables['System.TeamProject'], 'internal') }}:
-      name: NetCoreInternal-Pool
-      queue: BuildPool.Ubuntu.1604.Amd64
-    vmImage: ubuntu-16.04
-  steps:
-  - script: ./build.sh --skip-prereqs --configuration Debug --targets Default
-  - task: PublishTestResults@2
-    inputs:
-      testResultsFormat: VSTest
-      testResultsFiles: '**/*.trx'
-    condition: always()
-
 - job: debug_fedora27_x64
   displayName: fedora.27 x64 Debug Build
   pool:

build/LinuxDistrosNativeInstaller.props

@@ -1,7 +1,7 @@
 <Project>
   <ItemGroup>
-    <LinuxDistrosNeedNativeInstaller Include="debian.8-x64">
-      <DockerFolder>debian</DockerFolder>
+    <LinuxDistrosNeedNativeInstaller Include="ubuntu.18.04-x64">
+      <DockerFolder>ubuntu.18.04</DockerFolder>
       <InstallerExtension>deb</InstallerExtension>
       <DistroNameInInstaller>x64</DistroNameInInstaller>
     </LinuxDistrosNeedNativeInstaller>

scripts/docker/debian/Dockerfile

@@ -4,7 +4,7 @@
 #
 
 # Dockerfile that creates a container suitable to build dotnet-cli
-FROM microsoft/dotnet-buildtools-prereqs:ubuntu-18.04-f90bc20-20180320154721
+FROM mcr.microsoft.com/dotnet-buildtools/prereqs:ubuntu-18.04-debpkg-20210111135546-cfdd435
 
 RUN apt-get update && \
     apt-get -qqy install \