fix: fix docs error (#635)

## What ❔

fix docs error

## Why ❔

<!-- Why are these changes done? What goal do they contribute to? What
are the principles behind them? -->
<!-- Example: PR templates ensure PR reviewers, observers, and future
iterators are in context about the evolution of repos. -->

## Checklist

<!-- Check your PR fulfills the following items. -->
<!-- For draft PRs check the boxes as you complete them. -->

- [x] PR title corresponds to the body of PR (we generate changelog
entries from PRs).
- [x] Tests for the changes have been added / updated.
- [x] Documentation comments have been added / updated.
- [x] Code has been formatted via `zk fmt` and `zk lint`.
- [x] Spellcheck has been run via `cargo spellcheck
--cfg=./spellcheck/era.cfg --code 1`.

---------

Co-authored-by: Igor Aleksanov <[email protected]>
Co-authored-by: Igor Borodin <[email protected]>
Co-authored-by: AnastasiiaVashchuk <[email protected]>

core/tests/ts-integration/README.md

@@ -97,7 +97,7 @@ implemented, register them at [setup file](./src/jest-setup/add-matchers.ts) and
 ### Matcher modifiers
 
 `toBeAccepted` and `toBeRejected` matchers accept modifiers. You can see one (`shouldChangeETHBalances`) above. There
-are others (like `shouldChangeTokenBalances` or `shouldOnlyTakeFee`), and if needed you can create your onw ones.
+are others (like `shouldChangeTokenBalances` or `shouldOnlyTakeFee`), and if needed you can create your own ones.
 
 These modifiers would be applied to the transaction receipt, and you can implement any kind of custom logic there. To do
 so, you just need to declare a class that inherits `MatcherModifier` class and implements the `check` method.