feat: add tx hash to dao entity in subgraph

Description

Pr for adding the tx hash field in the subgraph Dao entity.

See the framework lifecycle in packages/contracts/docs/framework-lifecycle to decide what kind of change this pull request is.

[ ] Bug fix (non-breaking change which fixes an issue)
[ ] New feature (non-breaking change which adds functionality)
[ ] Breaking change (fix or feature that would cause existing functionality to not work as expected)

[ ] I have selected the correct base branch.
[ ] I have performed a self-review of my own code.
[ ] I have commented my code, particularly in hard-to-understand areas.
[ ] My changes generate no new warnings.
[ ] Any dependent changes have been merged and published in downstream modules.
[ ] I ran all tests with success and extended them if necessary.
[ ] I have updated the CHANGELOG.md file in the root folder.
[ ] I have updated the DEPLOYMENT_CHECKLIST file in the root folder.
[ ] I have updated the UPDATE_CHECKLIST file in the root folder.
[ ] I have updated the Subgraph and added a QA URL to the description of this PR.