Roll Out: Refactor GitHub handle in project files

### Dependency
- [ ] https://github.com/hackforla/website/issues/5441
- [ ] https://github.com/hackforla/website/issues/8428

### Overview
We need to define a single variable `github-handle` to hold the github handle for each member of the leadership team, to replace the `github` and `picture` variables which both hold urls that contain the github handle. Afterwards, the code displaying the leadership team can be modified to use the new variable, and the variables `github` and `picture` can be removed.

### Files to add handles
- [ ] 100-automations.md
- [ ] 311-data.md
- [ ] access-the-data.md
- [ ] adopt-civic-art.md
- [ ] ballot-nav.md
- [ ] brigade-organizers-playbook.md
- [ ] civic-opportunity-project.md
- [ ] civic-tech-index.md
- [ ] civic-tech-jobs.md
- [ ] civic-tech-structure.md
- [ ] criminal-sentencing.md
- [ ] curbmap.md
- [ ] design-systems.md
- [ ] ems-triage-tracker.md
- [ ] engage.md
- [ ] expunge-assist.md
- [ ] food-oasis.md
- [ ] green-earth-os.md
- [ ] guides-team.md
- [ ] heart.md
- [ ] hellogov.md
- [ ] home-unite-us.md
- [ ] jobs-for-hope.md
- [ ] light-the-way.md
- [ ] lucky-parking.md
- [ ] metro-ontime.md
- [ ] new-schools-today.md
- [ ] not-today.md
- [ ] open-community-survey.md
- [ ] public-tree-map.md
- [ ] shared-housing-project.md
- [ ] spare.md
- [ ] tdm-calculator.md
- [ ] tech-work-experience.md
- [ ] undebate.md
- [ ] vrms.md
- [ ] website.md
- [ ] work-for-la.md
- [ ] writeforall.md
- [ ] youthjusticenav.md

### Files to edit code
- [ ] assets\js/project.js

### Roll Out Plan

- [x] #5441
- [ ] Create issues to populate the github-handle variable for leadership teams

After the above issues are all closed:
- [ ] Create Issue: Modify code that displays the leadership team to use the new `github-handle` variable

After the above issues are all closed:

- [ ] Create issues to remove the `github` and `picture` variables.

### Resources/Instructions
https://github.com/hackforla/website/wiki/project.md-file-template
https://jekyllrb.com/