Create new user and group for arcvm_data_migrator

BUG=b:251764421
TEST=./display-accts.py --lint
TEST=With crrev.com/c/3932404, crrev.com/c/3963808 and
TEST=crrev.com/i/5048240, images built with build_image has
TEST=arcvm_data_migrator in /etc/{passwd,group}

Change-Id: I44cf3fb7ca2d21b57858333fd9ad2322b396e366
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/overlays/eclass-overlay/+/3960649
Reviewed-by: Ryo Hashimoto <hashimoto@chromium.org>
Tested-by: Momoko Hattori <momohatt@chromium.org>
Reviewed-by: Jorge Lucangeli Obes <jorgelo@chromium.org>
Commit-Queue: Momoko Hattori <momohatt@chromium.org>
diff --git a/profiles/base/accounts/group/arcvm_data_migrator b/profiles/base/accounts/group/arcvm_data_migrator
new file mode 100644
index 0000000..e0a957b
--- /dev/null
+++ b/profiles/base/accounts/group/arcvm_data_migrator
@@ -0,0 +1,3 @@
+group:arcvm_data_migrator
+gid:20198
+users:arcvm_data_migrator
diff --git a/profiles/base/accounts/user/arcvm_data_migrator b/profiles/base/accounts/user/arcvm_data_migrator
new file mode 100644
index 0000000..f72a6fd
--- /dev/null
+++ b/profiles/base/accounts/user/arcvm_data_migrator
@@ -0,0 +1,6 @@
+user:arcvm_data_migrator
+uid:20198
+gid:20198
+gecos:ChromeOS ARCVM /data migrator
+home:/dev/null
+shell:/bin/false