ci: Reduce file size of cabal and stack based builds

By passing -split-sections to all dependencies, GHC will link only the
modules we actually use and not the full package for each dependency.
This does neither work on MacOS nor Windows, thus we don't do it for
stack right now.

Stripping unused symbols in CI will further decrease the size of those files.

.github/scripts/arm/build.sh

@@ -55,10 +55,14 @@ cd ~/$SCRIPT_DIR
 git clone https://github.com/PostgREST/postgrest.git
 cd postgrest
 git checkout $PGRST_GITHUB_COMMIT
+cp cabal.project.non-nix cabal.project
 cabal v2-update && cabal v2-build
 
-# Copy the built binary to the Dockerfile directory
+# Strip unused symbols from executable
 PGRST_BIN=$(cabal exec which postgrest | tail -1)
+strip $PGRST_BIN
+
+# Copy the built binary to the Dockerfile directory
 cp $PGRST_BIN ~/$DOCKER_BUILD_DIR
 
 # Move and compress the built binary