Launch all Buildbucket builds in "realms-aware mode".

The 30% experiment appears to be fine (based on server logs).

R=gbeaty@chromium.org
BUG=1136313

Change-Id: I2b841cb31bdb15a3317a5ea43a4736efaf0d33a6
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2472700
Commit-Queue: Vadim Shtayura <vadimsh@chromium.org>
Reviewed-by: Garrett Beaty <gbeaty@chromium.org>
Cr-Commit-Position: refs/heads/master@{#817241}

infra/config/main.star

@@ -118,8 +118,8 @@ luci.realm(
     ],
 )
 
-# Launch a portion of Swarming tasks in "realms-aware mode", crbug.com/1136313.
-luci.builder.defaults.experiments.set({"luci.use_realms": 30})
+# Launch Swarming tasks in "realms-aware mode", crbug.com/1136313.
+luci.builder.defaults.experiments.set({"luci.use_realms": 100})
 
 exec("//swarming.star")