Error when executing npm command in firebase cloud functions

I’ve a project with the following folder structure:
enter image description here
It has a firebase cloud functions folder as well as a react app.

Here’s the code for the index.js file in the functions folder:

const functions = require("firebase-functions");
const { exec } = require("child_process");
const util = require("util");
const execPromise = util.promisify(exec);

exports.installModules = functions.https.onCall((data, context) => {
  return new Promise((resolve, reject) => {
    console.log("Starting install modules process");

    exec(
      "npm i",
      {
        cwd: "../react-app",
      },
      (err, stdout, stderr) => {
        if (err) {
          console.error("Error running build command:", err);
          reject(err);
        }

        console.log("Modules installed successfully with output:", stdout);
        resolve("Modules installed successfully");
      }
    );
  });
});

exports.build = functions.https.onCall((data, context) => {
  return new Promise((resolve, reject) => {
    console.log("Starting build process...");

    exec(
      "npm run build",
      {
        cwd: "../react-app",
      },
      (err, stdout, stderr) => {
        if (err) {
          console.error("Error running build command:", err);
          reject(err);
        }

        console.log("Build completed successfully with output:", stdout);
        resolve("Build completed successfully");
      }
    );
  });
});

The first function (installModules) installs modules inside the react app. The second function (build) makes a build folder for the react app. Both of these functions work fine when testing them with the firebase functions shell (with the command firebase functions:shell, and then nameOfFunction({}).

However, when running deploying these to the cloud I get the following error when calling them from a frontend.

**severity: "ERROR"
textPayload: "Unhandled error Error: spawn /bin/bash ENOENT
    at Process.ChildProcess._handle.onexit (node:internal/child_process:285:19)
    at onErrorNT (node:internal/child_process:485:16)
    at processTicksAndRejections (node:internal/process/task_queues:83:21) {
  errno: -2,
  code: 'ENOENT',
  syscall: 'spawn /bin/bash',
  path: '/bin/bash',
  spawnargs: [ '-c', 'npm i' ],
  cmd: 'npm i'
}**

I’ve tried running these in an express server deployed to both Google Cloud and Heroku but was running into too many issues which is why I decided to give firebase cloud functions a try. According to this post it is possible to run npm commands inside of a google function.

Thanks, any help is appreciated!