Slightly different syntax to specify mac build target, try to properly specify cibuildwheel version

.github/workflows/build_wheels.yml

diff --git a/.github/workflows/build_wheels.yml b/.github/workflows/build_wheels.yml
index 7fc0721..8e6f5cb 100644
--- a/.github/workflows/build_wheels.yml
+++ b/.github/workflows/build_wheels.yml
@@ -83,7 +83,7 @@
           platforms: arm64
 
       - name: Install Python dependencies
-        run: python -m pip install cibuildwheel>=${CIBUILDWHEEL_VERSION}
+        run: python -m pip install cibuildwheel>=${{ env.CIBUILDWHEEL_VERSION }}
 
       - name: Build wheels
         run: python -m cibuildwheel --output-dir dist

pyproject.toml

diff --git a/pyproject.toml b/pyproject.toml
index e73147d..cf4d8b7 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -39,5 +39,4 @@
 archs = ["x86_64", "arm64"]
 
 # Minimum version for proper C++17 support on MacOS
-[tool.cibuildwheel.macos.environment]
-MACOS_DEPLOYMENT_TARGET = "10.14"
+environment = { MACOSX_DEPLOYMENT_TARGET="10.14" }