Removing solution base README from 3-terrarium.

Deleting solution base README from 3-terrarium because no translation folder into solution.

Author: ManuSquall

.github/ISSUE_TEMPLATE/translations_checklist.md

@@ -32,7 +32,6 @@ assignees: ''
    - [ ] intro-to-css assignment
    - [ ] intro-to-DOM-and-closures README
    - [ ] intro-to-DOM-and-closures assignment
-   - [ ] solution base README
 - [ ] 4-typing-game base README
    - [ ] typing-game README
    - [ ] typing-game assignment