[Release] Add changelog and bump podspec bump following #220 (#222)

Author: ncooke3

CHANGELOG.md

@@ -1,3 +1,7 @@
+# 8.1.0
+- Add a utility to detect App Clips and make a semantic check for background
+  URL sessions. (#220)
+
 # 8.0.2
 - Fix default logging level regression introduced in 8.0.0 (no value set);
   default value is restored to `GULLoggerLevelNotice`. (#207)

GoogleUtilities.podspec

@@ -1,6 +1,6 @@
 Pod::Spec.new do |s|
   s.name             = 'GoogleUtilities'
-  s.version          = '8.0.2'
+  s.version          = '8.1.0'
   s.summary          = 'Google Utilities for Apple platform SDKs'
 
   s.description      = <<-DESC