Fix Typos in Documentation Files

[cypherpepe]

This pull request fixes various typos and minor grammatical issues across several documentation files. The changes improve readability and accuracy in the documentation. The following files were modified:

• importing.md: Corrected "mainnets" to "mainnets".
• usage.md: Corrected "accross" to "across".
• 1.ots.md: Corrected "trough" to "through".
• relay-validators.md: Corrected "where as" to "whereas".
• collection_migration.md: Corrected "Becasue" to "Because".

All changes were verified, and the documentation should now be free of these minor errors.

Commit Details

Each commit addresses a specific typo or grammatical issue in an individual file, ensuring clarity and focus on each change.