fix(grafana): use account email in Work Logs "Code commits" panel to fix 0-commit count for users with multiple accounts

[bujjibabukatta]

Fixes #8833

Problem

The "Code commits" panel in the Work Logs dashboard shows 0 commits when
a user's DevLake profile email differs from their GitHub account email.

Cause

The _accounts CTE was selecting u.email (DevLake user email) but the
join used c.author_id = a.email which expects the GitHub account email.

Fix

Changed u.email to a.email in the _accounts CTE so it correctly
uses the account email when matching commits.

Files Changed

• grafana/dashboards/mysql/work-logs.json
• grafana/dashboards/postgresql/work-logs.json