Backport PR jupyterlab#11339: Fix outdated clearSignalData reference (now Signal.clearData) (jupyterlab#11340)

Co-authored-by: Michał Krassowski <[email protected]>

Author: meeseeksmachine

docs/source/developer/patterns.rst

@@ -84,9 +84,9 @@ the payload. Signals should generally not be used to trigger the
 "default" behavior for an action, but to enable others to trigger
 additional behavior. If a "default" behavior is intended to be provided
 by another object, then a callback should be provided by that object.
-Wherever possible as signal connection should be made with the pattern
+Wherever possible a signal connection should be made with the pattern
 ``.connect(this._onFoo, this)``. Providing the ``this`` context enables
-the connection to be properly cleared by ``clearSignalData(this)``.
+the connection to be properly cleared by ``Signal.clearData(this)``.
 Using a private method avoids allocating a closure for each connection.
 
 Models