Laravel - 您的要求无法解析为可安装的软件包 - 任何想法？

Question

I'm trying to deploy my Laravel App on Google Cloud Platform using the command line gcloud app deploy.

I followed each step of this https://cloud.google.com/community/tutorials/run-laravel-on-appengine-flexible

Here's some logs :

Step #1: Using PHP version: 7.2
Step #1: Install PHP extensions...
Step #1: Running composer...
Step #1: Key post-install-cmd is a duplicate in ./composer.json at line 71
Step #1: Loading composer repositories with package information
Step #1: Installing dependencies from lock file
Step #1: Your requirements could not be resolved to an installable set of packages.
Step #1: 
Step #1:   Problem 1
Step #1:     - Installation request for phpoffice/phpspreadsheet 1.7.0 -> satisfiable by phpoffice/phpspreadsheet[1.7.0].
Step #1:     - phpoffice/phpspreadsheet 1.7.0 requires ext-gd * -> the requested PHP extension gd is missing from your system.
Step #1:   Problem 2
Step #1:     - phpoffice/phpspreadsheet 1.7.0 requires ext-gd * -> the requested PHP extension gd is missing from your system.
Step #1:     - maatwebsite/excel 3.1.13 requires phpoffice/phpspreadsheet ^1.6 -> satisfiable by phpoffice/phpspreadsheet[1.7.0].
Step #1:     - Installation request for maatwebsite/excel 3.1.13 -> satisfiable by maatwebsite/excel[3.1.13].
Step #1: 
Step #1:   To enable extensions, verify that they are enabled in your .ini files:
Step #1:     - /opt/php72/lib/php-cli.ini
Step #1:     - /opt/php72/lib/ext.enabled/ext-apcu-bc.ini
Step #1:     - /opt/php72/lib/ext.enabled/ext-mailparse.ini
Step #1:     - /opt/php72/lib/ext.enabled/ext-memcached.ini
Step #1:   You can also run `php --ini` inside terminal to see which files are used by PHP in CLI mode.
Step #1: error building image: error building stage: waiting for process to exit: exit status 2
Finished Step #1

• I'm on Windows 10 and I use the Google SDK to deploy.
• I use wamp64 I tried to uncomment extension=gd2 in every php.ini I have on my computer
• Here's a link of my PHP config
• I follow this, but it didn't worked.

I'm trying to use gcloud app deploy with the Google SDK to deploy my Laravel 5.5 app on an Bucket for my App Engine on Google Cloud Platform.