doc: fix a typo in the documentation

PR-URL: #16909
Reviewed-By: Anatoli Papirovski <apapirovski@mac.com>
Reviewed-By: Gireesh Punathil <gpunathi@in.ibm.com>

doc/api/deprecations.md

@@ -122,7 +122,7 @@ to the `constants` property exposed by the relevant module. For instance,
 Type: End-of-life
 
 Use of the [`crypto.pbkdf2()`][] API without specifying a digest was deprecated
-in Node.js 6.0 because the method defaulted to using the non-recommendend
+in Node.js 6.0 because the method defaulted to using the non-recommended
 `'SHA1'` digest. Previously, a deprecation warning was printed. Starting in
 Node.js 8.0.0, calling `crypto.pbkdf2()` or `crypto.pbkdf2Sync()` with an
 undefined `digest` will throw a `TypeError`.