build(deps): bump cachix/install-nix-action from 14 to 15

Dependencies

• [2] DVEPMQNI build(deps): bump cachix/install-nix-action from 13 to 14
• [3] NKPSTN6H add github ci tests
• [4] IBZKJGWS Bump cachix/install-nix-action from v10 to v12
• [5] IEL43MSU build(deps): bump cachix/install-nix-action from v12 to v13
• [6] 6WKHHS6H Bump cachix/install-nix-action from v8 to v10 (#791)

Change contents

• replacement in .github/workflows/test.yml at line 12
  [3.206]→[2.0:42](∅→∅)
  − - uses: cachix/install-nix-action@v14
  [3.206]

  [3.247]
  + - uses: cachix/install-nix-action@v15