Add ENVO-OEO mapping-file

[LillyG901]

Summary of the discussion

See #2010

The goal of this PR is to add a SSSOM file that includes previously via anotation property skos:closeMatch matched terms from ENVO. The match-type has been reassessed and often changed to skos:exactMatch. For the reasons of this change please check this table.

Type of change (CHANGELOG.md)

Add

• envo-oeo sssom file

Workflow checklist

Automation

Closes #

PR-Assignee

• [ ] 🐙 Follow the Pull Request Workflow
• [ ] 📝 Update the CHANGELOG.md
• [ ] 📙 Add #'s to term tracker annotation

Reviewer

• [ ] 🐙 Follow the Reviewer Guide
• [ ] 🐙 Provided feedback and show sufficient appreciation for the work done