Update iteration.md | Spelling

[as1605]

Minor spelling and grammar change

What is the purpose of the change

Fixes spelling errors in the documentation

Brief change log

• tarnsmitted to transmitted

Does this pull request potentially affect one of the following parts:

• Dependencies (does it add or upgrade a dependency): (no)
• The public API, i.e., is any changed class annotated with @Public(Evolving): (no)

Documentation

• Does this pull request introduce a new feature? (no)
• If yes, how is the feature documented? (not applicable)