Update gradle to 6.6.1

Contents of README.google:
Name: Gradle
URL: https://gradle.org/releases/
Version: 6.6.1
Revision: NA
License: Apache License Version 2.0

Description:
This is Gradle version 6.6.1 pulled directly from the website


Bug: 169692487
Change-Id: Id961fc10b3f374c9d83848e65d12923a8492167b
diff --git a/third_party/gradle/gradle.tar.gz.sha1 b/third_party/gradle/gradle.tar.gz.sha1
index a219d61..cbf0dd4 100644
--- a/third_party/gradle/gradle.tar.gz.sha1
+++ b/third_party/gradle/gradle.tar.gz.sha1
@@ -1 +1 @@
-4a07bcbff312d890bc1b96c39aaffdcab882cd3a
\ No newline at end of file
+6b27c3955e734eafafaa3d4e35c854a57c48b427
\ No newline at end of file