chore: use github ref name to update next version

[jiparis]

This PR solves the problem when the pushed tag is not the same as the one present in .chainloop.yaml, for example when pushing a patch. Taking the tag value instead of the one in the file, will make the behaviour consistent, avoiding extra PRs to fix the version.

Example (sed error is normal in MacOS):

> GITHUB_REF_NAME=v1.2.3 DEBUG=1 .github/workflows/utils/bump-project-version.sh
+ [[ -n 1 ]]
+ set -x
+ project_yaml=.chainloop.yml
+ [[ -n '' ]]
+ [[ -n v1.2.3 ]]
++ echo v1.2.3
++ awk '-F[ .]' '{print $1"."$2+1"."0}'
+ version=v1.3.0
+ sed -i 's#^projectVersion:.*#projectVersion: v1.3.0#g' .chainloop.yml
sed: 1: ".chainloop.yml": invalid command code .