assert: unlock the assert API

Change the Stability Index on `assert` from Locked to Stable.

PR-URL: #11304
Ref: #11200
Reviewed-By: Sam Roberts <[email protected]>
Reviewed-By: Michaël Zasso <[email protected]>
Reviewed-By: Gibson Fahnestock <[email protected]>
Reviewed-By: Joyee Cheung <[email protected]>
Reviewed-By: Luigi Pinca <[email protected]>
Reviewed-By: Сковорода Никита Андреевич <[email protected]>
Reviewed-By: Sakthipriyan Vairamani <[email protected]>
Reviewed-By: Evan Lucas <[email protected]>
Reviewed-By: Anna Henningsen <[email protected]>
Reviewed-By: James M Snell <[email protected]>

doc/api/assert.md

@@ -1,6 +1,6 @@
 # Assert
 
-> Stability: 3 - Locked
+> Stability: 2 - Stable
 
 The `assert` module provides a simple set of assertion tests that can be used to
 test invariants. The module is intended for internal use by Node.js, but can be