Revert "infra: Switch to "angle_2" presubmit config."

This reverts commit 5166a25b2c.

Reason for revert: Breaks presubmit tester (again).

Original change's description:
> infra: Switch to "angle_2" presubmit config.
>
> We will revert this once we remove the depot_tools config.
>
> Bug: angleproject:5114
> Change-Id: If922a24c9955ba5d5d30ec634fa6c3d6db177f65
> Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2831999
> Reviewed-by: Jamie Madill <jmadill@chromium.org>
> Commit-Queue: Jamie Madill <jmadill@chromium.org>

Bug: angleproject:5114
Change-Id: I7a540c728f6851151c2f708480de21ce41938111
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2836785
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Commit-Queue: Jamie Madill <jmadill@chromium.org>

infra/config/generated/cr-buildbucket.cfg

@@ -389,7 +389,7 @@ buckets {
         cipd_version: "refs/heads/master"
         cmd: "recipes"
       }
-      properties: "{\"recipe\":\"run_presubmit\",\"repo_name\":\"angle_2\",\"runhooks\":true}"
+      properties: "{\"recipe\":\"run_presubmit\",\"repo_name\":\"angle\",\"runhooks\":true}"
       build_numbers: YES
       service_account: "angle-try-builder@chops-service-accounts.iam.gserviceaccount.com"
     }

infra/config/main.star

@@ -242,7 +242,7 @@ luci.builder(
         "os": os.LINUX.dimension,
     },
     properties = {
-        "repo_name": "angle_2",
+        "repo_name": "angle",
         "runhooks": True,
     },
 )