ci: Add workflow to seed cachix (#2615)

Fixes #2609.

.github/workflows/ci.yaml

@@ -108,7 +108,6 @@ jobs:
       - name: Setup Nix Environment
         uses: ./.github/actions/setup-nix
         with:
-          authToken: '${{ secrets.CACHIX_AUTH_TOKEN }}'
           tools: tests
 
       - name: Build static executable
@@ -131,13 +130,6 @@ jobs:
           path: postgrest-docker.tar.gz
           if-no-files-found: error
 
-      - name: Build and push everything to Cachix (main branch only)
-        if: ${{ github.ref == 'refs/heads/main' }}
-        run: |
-          nix-build
-          nix-env -f default.nix -iA devTools
-          postgrest-push-cachix
-
 
   Build-Macos-Nix:
     name: Build MacOS (Nix)
@@ -146,18 +138,10 @@ jobs:
       - uses: actions/checkout@v3
       - name: Setup Nix Environment
         uses: ./.github/actions/setup-nix
-        with:
-          authToken: '${{ secrets.CACHIX_AUTH_TOKEN }}'
 
       - name: Build everything
         run: |
           nix-build
-          nix-env -f default.nix -iA devTools
-
-      - name: Push to Cachix (main branch only)
-        if: ${{ github.ref == 'refs/heads/main' }}
-        run: |
-          postgrest-push-cachix
 
 
   Build-Stack: