Pin Rust to 1.82.0 when building Python wheels (#17993)

Addresses step 1 of #17988.

.github/workflows/release-artifacts.yml

@@ -5,7 +5,7 @@ name: Build release artifacts
 on:
   # we build on PRs and develop to (hopefully) get early warning
   # of things breaking (but only build one set of debs). PRs skip
-  # building wheels on ARM.
+  # building wheels on macOS & ARM.
   pull_request:
   push:
     branches: ["develop", "release-*"]
@@ -111,7 +111,7 @@ jobs:
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        os: [ubuntu-22.04]
+        os: [ubuntu-22.04, macos-13]
         arch: [x86_64, aarch64]
         # is_pr is a flag used to exclude certain jobs from the matrix on PRs.
         # It is not read by the rest of the workflow.
@@ -119,6 +119,12 @@ jobs:
           - ${{ startsWith(github.ref, 'refs/pull/') }}
 
         exclude:
+          # Don't build macos wheels on PR CI.
+          - is_pr: true
+            os: "macos-13"
+          # Don't build aarch64 wheels on mac.
+          - os: "macos-13"
+            arch: aarch64
           # Don't build aarch64 wheels on PR CI.
           - is_pr: true
             arch: aarch64

changelog.d/17993.misc

@@ -0,0 +1 @@
+Fix building wheels for MacOS which was temporarily disabled in Synapse 1.120.2.

pyproject.toml

@@ -386,8 +386,11 @@ build-backend = "poetry.core.masonry.api"
 #    c.f. https://github.com/matrix-org/synapse/pull/14259
 skip = "cp36* cp37* cp38* pp37* pp38* *-musllinux_i686 pp*aarch64 *-musllinux_aarch64"
 
-# We need a rust compiler
-before-all =  "curl https://sh.rustup.rs -sSf | sh -s -- --default-toolchain stable -y --profile minimal"
+# We need a rust compiler.
+#
+# We temporarily pin Rust to 1.82.0 to work around
+# https://github.com/element-hq/synapse/issues/17988
+before-all =  "curl https://sh.rustup.rs -sSf | sh -s -- --default-toolchain 1.82.0 -y --profile minimal"
 environment= { PATH = "$PATH:$HOME/.cargo/bin" }
 
 # For some reason if we don't manually clean the build directory we