Update Guava to version 31.0.1-jre

Change-Id: I796c10397aff3a605a2c1608a34301109791e5fb
diff --git a/build.gradle b/build.gradle
index 2045d5a..0d328cf 100644
--- a/build.gradle
+++ b/build.gradle
@@ -38,7 +38,7 @@
     asmVersion = '9.2'  // When updating update tools/asmifier.py and Toolhelper as well.
     espressoVersion = '3.0.0'
     fastutilVersion = '7.2.0'
-    guavaVersion = '30.1.1-jre'
+    guavaVersion = '31.0.1-jre'
     joptSimpleVersion = '4.6'
     gsonVersion = '2.7'
     junitVersion = '4.13-beta-2'