tests: remove usage of undeclared runtime dependencies

tests/default.nix

@@ -8,9 +8,21 @@ let
     nixOnDroidChannelURL = "file:///n-o-d/archive.tar.gz";
     nixOnDroidFlakeURL = "/n-o-d/unpacked";
   };
+
+  pkgs = nixpkgs.legacyPackages.${system};
+
+  runtimePackages = with pkgs; [
+    coreutils
+    git
+    gnutar
+    gzip
+    unzip
+    wget
+    zip
+  ];
 in
 
-nixpkgs.legacyPackages.${system}.runCommand
+pkgs.runCommand
   "fakedroid"
 {
   preferLocalBuild = true;
@@ -20,6 +32,8 @@ nixpkgs.legacyPackages.${system}.runCommand
     install -D -m755  ${./fakedroid.sh} $out
 
     substituteInPlace $out \
+      --subst-var-by bash "${pkgs.bash}" \
+      --subst-var-by path "${pkgs.lib.makeBinPath runtimePackages}" \
       --subst-var-by bootstrapZip "${bootstrap.customPkgs.bootstrapZip}" \
       --subst-var-by prootTest "${bootstrap.customPkgs.prootTermuxTest}" \
       --subst-var-by installationDir "${bootstrap.config.build.installationDir}" \

tests/fakedroid.sh

@@ -1,4 +1,4 @@
-#!/usr/bin/env bash
+#!@bash@/bin/bash
 
 # This is a script to run "on-device" tests in CI, without the device.
 # Takes the bootstrap aarch64 zipball, unpacks, proots into it.
@@ -8,6 +8,8 @@
 
 set -ueo pipefail
 
+PATH=@path@
+
 USE_FLAKE="${USE_FLAKE:-0}"
 if [[ ! "$USE_FLAKE" =~ ^[01]$ ]]; then
     echo "USE_FLAKE environment variable needs to be either 0 or 1, got '$USE_FLAKE'."