Auto merge of #23022 - servo:jdm-patch-29, r=SimonSapin

Route all trychooser tasks to servo-try.

Fixes #23020. Maybe this will deal with https://github.com/servo/homu/issues/191 as well?

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.taskcluster.yml

@@ -60,8 +60,8 @@ tasks:
                   $let:
                     treeherder_repo:
                       $if: "branch[:4] == 'try-'"
-                      then: "servo-${branch}"
-                      else: "servo-try"
+                      then: "servo-try"
+                      else: "servo-${branch}"
                   in:
                     - "tc-treeherder.v2._/${treeherder_repo}.${event.after}"
                     - "tc-treeherder-staging.v2._/${treeherder_repo}.${event.after}"