chore: remove power assert (#384)

This is a dev dependency that seems to be unused. Currently it is
pulling in a transitive dependency that is preventing us from using `npm
ci` in our workflows.

Author: matthewrobertson

docs/generated/api.json

@@ -1,7 +1,7 @@
 {
   "metadata": {
     "toolPackage": "@microsoft/api-extractor",
-    "toolVersion": "7.18.16",
+    "toolVersion": "7.18.19",
     "schemaVersion": 1004,
     "oldestForwardsCompatibleVersion": 1001,
     "tsdocConfig": {