Try fixing syntax

Author: znicholls

.github/workflows/install-pypi.yaml

@@ -18,6 +18,7 @@ on:
 jobs:
   test-pypi-install:
     name: Test PyPI install ${{ matrix.install-target }} (${{ matrix.python-version }}, ${{ matrix.os }})
+    runs-on: "${{ matrix.os }}"
     strategy:
       fail-fast: false
       matrix:
@@ -26,9 +27,9 @@ jobs:
         python-version: [ "3.9", "3.10", "3.11", "3.12", "3.13" ]
         # Check both 'library' install and the 'application' (i.e. locked) install
         install-target: ["example-fgen-basic", "example-fgen-basic[locked]"]
-        # TODO: consider adding other compilers to our matrix
-        # (see https://github.com/fortran-lang/setup-fortran)
         toolchain:
+          # TODO: consider adding other compilers to our matrix
+          # (see https://github.com/fortran-lang/setup-fortran)
           - {compiler: gcc, version: 13}
           # # Only seems to be available on Mac for some reason,
           # # maybe it will be available when latest images are updated.
@@ -40,7 +41,6 @@ jobs:
           - pip-install-flags: "--no-binary example-fgen-basic"
             python-version: "3.11"
 
-    runs-on: "${{ matrix.os }}"
     steps:
     - name: Set up Python "${{ matrix.python-version }}"
       id: setup-python