horizon: pin pip to <25.3

Closes-Bug: #2129916

Change-Id: Ib1b40a65cb2667b53c72f00d16bfe280bcf24bfe
Signed-off-by: Michal Nasiadka <[email protected]>
(cherry picked from commit 9bc8d4d)

Author: mnasiadka

docker/horizon/Dockerfile.j2

@@ -50,6 +50,7 @@ COPY extend_start.sh /usr/local/bin/kolla_extend_start
 # because we are using different distros with different python version and we need to
 # know to which path symlink should point to.
 RUN ln -s horizon-source/* horizon \
+    && {{ macros.install_pip(['pip==25.2.*']) }} \
     && {{ macros.upper_constraints_remove("horizon") }} \
     && {{ macros.install_pip(horizon_pip_packages | customizable("pip_packages")) }} \
     && mkdir -p /etc/openstack-dashboard \