Revert the changes to Pester from merged PR PowerShell#4184 (PowerShell#4881)

TravisEz13 · daxian-dbw · commit 4c6ad4a13371 · 2017-09-20T16:08:29.000-07:00
That PR incorrectly included Pester changes. Most likely because that individual did not update his submodules.
diff --git a/src/Modules/Shared/Pester b/src/Modules/Shared/Pester
@@ -1 +1 @@
-Subproject commit 51f1597eae5e517ce65fed293c9d6e245b1a9d60
+Subproject commit aa243108e7da50a8cf82513b6dd649b653c70b0e
