Update CAST 2026 status: add Early Bird Registration link

[Copilot]

Adds Early Bird Registration info to CAST 2026 status while preserving the existing CFP link.

Conference/Workshop Details

• Name, Location, Date(s), Website URL and Status are required
• X / Twitter is Optional
• Location should be City + Country or Online
• Status can include information about registration, pricing, calls for proposals and can include links to all the above.

Status field updated to:

status: <a href="https://sessionize.com/association-for-software-testing-cast/" target="_blank">CFP is Open</a> until May 31, 2026. <a href="https://associationforsoftwaretesting.org/conference/cast-2026/cast-2026-packages-pricing/?utm_source=testingconferences" target="_blank">Early Bird Registration is Open</a> until June 1, 2026

Checklist

• I have added the conference/workshop to the correct YAML file (_data/current.yml or _data/past.yml)
• The entry includes name, location, date(s), url and accurate status
• The entry is in chronological order (soonest to furtherest away)
• If there are any special characters in the name field (: or ; or '), the name must be in quotes (")
• I have checked for duplicates to avoid listing the same event twice
• Build runs successfully

Additional context

No structural changes — only the status field for CAST 2026 was modified.