1.37.0 fails to build in my build environment (Ubuntu 18.04 in LXC) with this error:

ubuntu@mattermost-mobile:~/mattermost-mobile$ npm run build:android

> mattermost-mobile@1.37.0 build:android /home/ubuntu/mattermost-mobile
> ./scripts/build.sh apk

./scripts/build.sh: 3: ./scripts/build.sh: Syntax error: "(" unexpected
npm ERR! code ELIFECYCLE
npm ERR! errno 2
npm ERR! mattermost-mobile@1.37.0 build:android: `./scripts/build.sh apk`
npm ERR! Exit status 2
npm ERR! 
npm ERR! Failed at the mattermost-mobile@1.37.0 build:android script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.

npm ERR! A complete log of this run can be found in:
npm ERR!     /home/ubuntu/.npm/_logs/2020-11-14T11_47_00_288Z-debug.log

The top of that file, build.sh, refers to /bin/sh, but on Ubuntu and Debian, /bin/sh has been Dash for quite a while, whereas build.sh seems to written for Bash (where function is a valid keyword):

ubuntu@mattermost-mobile:~/mattermost-mobile$ head scripts/build.sh 
#!/bin/sh

function execute() {
    cd fastlane && NODE_ENV=production bundle exec fastlane $1 $2
}

I suggest switching the shebang to #/bin/bash, or better yet, #!/usr/bin/env bash (for path-agnosticity). In my environment, using either one fixes the build.