Refresh for 2025.1 release

Summary of changes:

- Update snap version and branch for upper constraints.
- Update .gitreview defaultbranch
- Drop nova binary entry point as it has been dropped in the
  respective projects.

Change-Id: Ib4b6fbe64f474a0234eadcda0888c3f34c438428

.gitreview

@@ -2,3 +2,4 @@
 host=review.opendev.org
 port=29418
 project=x/snap-openstackclients.git
+defaultbranch=stable/2025.1

snapcraft.yaml

@@ -1,5 +1,5 @@
 name: openstackclients
-version: "2024.1"
+version: "2025.1"
 summary: OpenStack Client tools
 description: |
   OpenStackClient (aka OSC) is a command-line client for OpenStack
@@ -49,12 +49,6 @@ apps:
     plugs:
       - network
       - home
-  nova:
-    command: bin/nova
-    plugs:
-      - network
-      - home
-      - ssh-public-keys
   cinder:
     command: bin/cinder
     plugs:
@@ -176,7 +170,7 @@ parts:
       - setuptools-rust
       - Cython
     python-constraints:
-      - https://raw.githubusercontent.com/openstack/requirements/stable/2024.1/upper-constraints.txt
+      - https://raw.githubusercontent.com/openstack/requirements/stable/2025.1/upper-constraints.txt
     build-packages:
       - libffi-dev
       - libkrb5-dev