Update Guava to 29.0

To allow us to start using Duration with com.google.common.util.concurrent;
note that com.google.common.util.concurrent.internal.InternalFutureFailureAccess -
which we do use - has been split out into a separate jar by Guava upstream.

Due to historical repo/testing infrastructure setup, we cannot update
third_party jars in the same PR as non-third_party sources. We therefore
have to keep the old Guava 25.1 jars to allow scripts/bootstrap/compile.sh
(which explicitly references version 25.1) to continue to run, and to allow
//src/test/shell/bazel:bazel_bootstrap_distfile_test to continue to pass.

As an immediate followup to this PR, we will have to

1. update compile.sh to use Guava 29.0 (and the new failureaccess jar); and
2. remove Guava 25.1 jars.

Closes https://github.com/bazelbuild/bazel/pull/10394

RELNOTES: None.

third_party/BUILD

diff --git a/third_party/BUILD b/third_party/BUILD
index 3b918e3..2bc5b7a 100644
--- a/third_party/BUILD
+++ b/third_party/BUILD
@@ -455,7 +455,10 @@
 distrib_java_import(
     name = "guava",
     enable_distributions = ["debian"],
-    jars = ["guava/guava-25.1-jre.jar"],
+    jars = [
+        "guava/failureaccess-1.0.1.jar",
+        "guava/guava-29.0-jre.jar",
+    ],
     exports = [
         ":error_prone_annotations",
         ":jcip_annotations",
@@ -503,7 +506,7 @@
 # For bootstrapping JavaBuilder
 distrib_jar_filegroup(
     name = "guava-jars",
-    srcs = ["guava/guava-25.1-jre.jar"],
+    srcs = ["guava/guava-29.0-jre.jar"],
     enable_distributions = ["debian"],
 )
 
@@ -620,7 +623,7 @@
 
 java_import(
     name = "guava-testlib",
-    jars = ["guava/guava-testlib-25.1-jre.jar"],
+    jars = ["guava/guava-testlib-29.0-jre.jar"],
 )
 
 java_import(