Upgrade http client to 1.29.0. (#235)

Author: kolea2

pom.xml

@@ -44,7 +44,7 @@
 
   <properties>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-    <project.google.http.version>1.27.0</project.google.http.version>
+    <project.google.http.version>1.29.0</project.google.http.version>
     <project.junit.version>4.12</project.junit.version>
     <project.guava.version>27.1-android</project.guava.version>
     <project.appengine.version>1.9.71</project.appengine.version>