Update docker image to 18.04 (#31722)

John Luo · web-flow · commit 22cdfd666d7b · 2021-04-12T14:07:22.000-07:00
diff --git a/eng/docker/ubuntu-alpine37.Dockerfile b/eng/docker/ubuntu-alpine37.Dockerfile
@@ -1,4 +1,4 @@
-FROM mcr.microsoft.com/dotnet-buildtools/prereqs:ubuntu-16.04-cross-arm64-alpine10fcdcf-20190208200917
+FROM mcr.microsoft.com/dotnet-buildtools/prereqs:ubuntu-18.04-cross-arm64-alpine-85814b7-20200327151156
 ARG USER
 ARG USER_ID
 ARG GROUP_ID

Original file line number	Diff line number	Diff line change
`@@ -1,4 +1,4 @@`
`1`		`-FROM mcr.microsoft.com/dotnet-buildtools/prereqs:ubuntu-16.04-cross-arm64-alpine10fcdcf-20190208200917`
	`1`	`+FROM mcr.microsoft.com/dotnet-buildtools/prereqs:ubuntu-18.04-cross-arm64-alpine-85814b7-20200327151156`
`2`	`2`	`ARG USER`
`3`	`3`	`ARG USER_ID`
`4`	`4`	`ARG GROUP_ID`