chore: update docs

Author: rax-it

packages/@lwc/engine-core/README.md

@@ -116,6 +116,6 @@ This experimental API enables the sanitization of HTML content by external servi
 
 This experimental API enables the removal of an object's observable membrane proxy wrapper.
 
-### addTrustedSignal()
+### setSignalValidator()
 
-This experimental API enables the addition of a signal as a trusted signal. If the [`ENABLE_EXPERIMENTAL_SIGNALS`](https://github.com/salesforce/lwc/blob/master/packages/%40lwc/features/README.md#lwcfeatures) feature is enabled, the signal will be added to the set of trusted signals, rendering engine will track the value of the signal hence causing a re-render when the signal value changes.
+This experimental API enables the addition of a signal as a trusted signal. If the [`ENABLE_EXPERIMENTAL_SIGNALS`](https://github.com/salesforce/lwc/blob/master/packages/%40lwc/features/README.md#lwcfeatures) feature is enabled, any signal value change will trigger a re-render.