Remove the deprecated tempest-account-generator CLI

Tempest CLI tempest-account-generator was deprecated
4 years ago.
devstack still uses the deprecated CLI for which
patch has been proposed.

As deprecation is done long time back,
'tempest-account-generator' should be now used as
'tempest account-generator'

The following commit gives the idea of deprecation
message:-
https://opendev.org/openstack/tempest/commit/68b8b9d26fae5c07fa7c4c443e4b0ca51ad98258

Depends-on: I624e1dc57a3d3533322fb298c01f70241d0400ed
Signed-off by: Soniya Vyas<svyas@redhat.com>
Change-Id: I7c18998dd877d7fd065e4d1d0950b6f6413587c3
diff --git a/releasenotes/notes/account_generator-6eb03f664a448c35.yaml b/releasenotes/notes/account_generator-6eb03f664a448c35.yaml
new file mode 100644
index 0000000..ade632f
--- /dev/null
+++ b/releasenotes/notes/account_generator-6eb03f664a448c35.yaml
@@ -0,0 +1,7 @@
+---
+upgrade:
+  - |
+    Remove the deprecated CLI ``tempest-account-generator`` in favor of
+    ``tempest account-generator`` command.
+    You can use ``tempest account-generator`` CLI to generate the accounts
+    yaml file.