bazel: Increase bes_timeout

We hit a failure in CI that may have been caused by this timeout being
too short.

Also remove a duplicate flag.

Bug: 365796228
Change-Id: I523959d1c53e9030f60306dfe8786b33a0a587dc
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/234992
Docs-Not-Needed: Ted Pudlik <tpudlik@google.com>
Lint: Lint 🤖 <android-build-ayeaye@system.gserviceaccount.com>
Reviewed-by: Rob Mohr <mohrr@google.com>
Commit-Queue: Ted Pudlik <tpudlik@google.com>

.bazelrc

@@ -181,9 +181,8 @@ common:remote_cache --google_default_credentials=true
 common:remote_cache --remote_instance_name=projects/pigweed-rbe-open/instances/default-instance
 common:remote_cache --remote_upload_local_results=false
 common:remote_cache --bes_backend="buildeventservice.googleapis.com"
-common:remote_cache --bes_timeout=60s
+common:remote_cache --bes_timeout=600s
 common:remote_cache --bes_results_url="https://source.cloud.google.com/results/invocations/"
-common:remote_cache --remote_instance_name=projects/pigweed-rbe-open/instances/default-instance
 common:remote_cache --bes_instance_name=pigweed-rbe-open
 
 # Specifies desired output mode for running tests.