Add RUSTC_BOOTSTRAP

- Prevents VSCode from rebuilding everything during tests

Author: emlautarom1

flake.nix

@@ -35,6 +35,7 @@
           chmod +x .githooks/* && git config --local core.hooksPath .githooks/
         '';
 
+        RUSTC_BOOTSTRAP = "1";
         LD_LIBRARY_PATH = pkgs.lib.makeLibraryPath [ pkgs.openssl ];
         PKG_CONFIG_PATH = "${pkgs.openssl.dev}/lib/pkgconfig";
       };