Regenerate the LUCI config for a new minimum version of lucicfg.

The presubmit check uses the most recent version, which was resulting in
different output for cq-builders.md. It also ow warns about
crbug.com/1054172 being an unknown experiement.

Change-Id: I323a9474df1824bfbc61a892aad75899a0055945
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2642188
Auto-Submit: Garrett Beaty <gbeaty@chromium.org>
Reviewed-by: Ben Pastene <bpastene@chromium.org>
Commit-Queue: Ben Pastene <bpastene@chromium.org>
Cr-Commit-Position: refs/heads/master@{#845825}

infra/config/generated/cq-builders.md

@@ -374,7 +374,7 @@ by CQ. These are often used to test new configurations before they are added
 as required builders.
 
 * [linux-perfetto-rel](https://ci.chromium.org/p/chromium/builders/try/linux-perfetto-rel) ([definition](https://cs.chromium.org/search?q=package:%5Echromium$+file:/cq.star$+-file:/beta/+-file:/stable/+linux-perfetto-rel)) ([matching builders](https://cs.chromium.org/search?q=+file:trybots.py+linux-perfetto-rel))
-  * Experiment percentage: 100
+  * Experiment percentage: 100.0
 
   Path regular expressions:
   * [`//base/trace_event/.+`](https://cs.chromium.org/chromium/src/base/trace_event/)
@@ -384,5 +384,5 @@ as required builders.
   * [`//services/tracing/.+`](https://cs.chromium.org/chromium/src/services/tracing/)
 
 * [linux-rel-builderful](https://ci.chromium.org/p/chromium/builders/try/linux-rel-builderful) ([definition](https://cs.chromium.org/search?q=package:%5Echromium$+file:/cq.star$+-file:/beta/+-file:/stable/+linux-rel-builderful)) ([matching builders](https://cs.chromium.org/search?q=+file:trybots.py+linux-rel-builderful))
-  * Experiment percentage: 5
+  * Experiment percentage: 5.0
 

infra/config/main.star

@@ -10,16 +10,13 @@ load("//lib/branches.star", "branches")
 load("//project.star", "settings")
 
 lucicfg.check_version(
-    min = "1.19.0",
+    min = "1.21.5",
     message = "Update depot_tools",
 )
 
 # Enable LUCI Realms support.
 lucicfg.enable_experiment("crbug.com/1085650")
 
-# Enable tree closing.
-lucicfg.enable_experiment("crbug.com/1054172")
-
 # Tell lucicfg what files it is allowed to touch
 lucicfg.config(
     config_dir = "generated",