CI: clean up workflow files.

We used to have to use environment variables to pass through to
github/scripts/build.sh, but now we run ./configure directly it's
clearer to use explicit flags (though some matrixes still use env vars
for simplicity).

We also don't need to set COMPAT, as it's the default (MacOS tests
that we build without it, but otherwise we assume it's on).

And we make `gather` actually depend on all the other steps!

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

.github/workflows/macos.yaml

@@ -7,10 +7,6 @@ jobs:
     name: Smoke Test macOS
     runs-on: macos-latest
     timeout-minutes: 120
-    env:
-      DEVELOPER: 1
-      VALGRIND: 0
-      COMPAT: 0
     strategy:
       fail-fast: true
     steps:
@@ -39,10 +35,6 @@ jobs:
 
       - name: Build
         env:
-          VALGRIND: ${{ matrix.VALGRIND }}
-          DEVELOPER: ${{ matrix.DEVELOPER }}
-          COMPILER: ${{ matrix.COMPILER }}
-          COMPAT: ${{ matrix.COMPAT }}
           PYTEST_PAR: ${{ matrix.PYTEST_PAR }}
           PYTEST_OPTS: ${{ matrix.PYTEST_OPTS }}
           NO_PYTHON: ${{ matrix.NO_PYTHON }}
@@ -63,5 +55,5 @@ jobs:
               slow_test: marks tests as slow (deselect with '-m "not slow_test"')
           EOF
 
-          python3.10 -m poetry run ./configure
+          python3.10 -m poetry run ./configure --enable-developer --disable-valgrind --disable-compat
           python3.10 -m poetry run make