use same permissions for release assets

[kranurag7]

As of now, When we generate cluster-stacks using csctl then we get the following:

$ eza -halo releases/docker-ferrol-1-27-v3/
Octal Permissions Size User Date Modified Name
0755  .rwxr-xr-x@  140 k7   24 Feb 01:03  cluster-addon-values.yaml
0644  .rw-r--r--@  10k k7   24 Feb 01:03  docker-ferrol-1-27-cluster-addon-v3.tgz
0644  .rw-r--r--@ 2.6k k7   24 Feb 01:03  docker-ferrol-1-27-cluster-class-v3.tgz
0644  .rw-r--r--@  143 k7   24 Feb 01:03  hashes.json
0644  .rw-r--r--@  170 k7   24 Feb 01:03  metadata.yaml

In the above release assets, we have totally different permission for cluster-addon-values.yaml file.
This issue tracks fixing the permissions so that we have same permission for cluster-addon-values.yaml as well.

/kind proposal