Bug 1566309 - Upgrade mac builds to rust 1.36. r=chmanchester

Differential Revision: https://phabricator.services.mozilla.com/D38156

--HG--
extra : moz-landing-system : lando

taskcluster/ci/toolchain/rust.yml

@@ -135,7 +135,7 @@ linux64-rust-macos-1.34:
 linux64-rust-macos-1.35:
     description: "rust repack with macos-cross support"
     treeherder:
-        symbol: TL(rust-macos)
+        symbol: TL(rust-macos-1.35)
     run:
         arguments: [
             '--channel', '1.35.0',
@@ -143,6 +143,18 @@ linux64-rust-macos-1.35:
             '--target', 'x86_64-unknown-linux-gnu',
             '--target', 'x86_64-apple-darwin',
         ]
+
+linux64-rust-macos-1.36:
+    description: "rust repack with macos-cross support"
+    treeherder:
+        symbol: TL(rust-macos)
+    run:
+        arguments: [
+            '--channel', '1.36.0',
+            '--host', 'x86_64-unknown-linux-gnu',
+            '--target', 'x86_64-unknown-linux-gnu',
+            '--target', 'x86_64-apple-darwin',
+        ]
         toolchain-alias: linux64-rust-macos
 
 linux64-rust-nightly-macos: