Fix typos in ts files as per Fossies source code check

[jost-s]

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Description

Fixes typos in source code files found by Fossies source code check

Evan asked me to:

• fix all of the errors in the ts/ directory, except for exceptions.json
• fix the one typo in stylesheets/_modules.scss. "tht" should be "the"
• don't fix any of the errors in any of the other folders yet (ignore test/, libtextsecure/, js/, and app/)

[EvanHahn-Signal]

Looks good! I think this needs a rebase with development (we recently pushed some stuff) and then this is good to go.

[jost-s]

Rebased (there's no way around a force-push, is there?)

[EvanHahn-Signal]

Don't think there's a way around a force push (though git push --force-with-lease is usually safe).

This looks good. Thanks for doing it!