Cannot manually test Commerce due to bcmath extension

I have this same issue:

I tried installing eca_commerce which depends on commerce and got this error:

This may be the error:

Updating dependencies
Your requirements could not be resolved to an installable set of packages.

  Problem 1
    - drupal/commerce[2.0.0-alpha1, ..., 2.0.0-alpha3] require drupal/core ^8 -> found drupal/core[8.0.0-beta6, ..., 8.9.x-dev] but it conflicts with your root composer.json require (10.2.x-dev).
    - drupal/commerce 2.0.0-alpha4 requires drupal/core ~8.1 -> found drupal/core[8.1.0-beta1, ..., 8.9.x-dev] but it conflicts with your root composer.json require (10.2.x-dev).
    - drupal/commerce[2.0.0-beta1, ..., 2.0.0-beta6] require drupal/core ~8.2 -> found drupal/core[8.2.0-beta1, ..., 8.9.x-dev] but it conflicts with your root composer.json require (10.2.x-dev).
    - drupal/commerce[2.0.0-beta7, ..., 2.0.0] require drupal/core ~8.3 -> found drupal/core[8.3.0-alpha1, ..., 8.9.x-dev] but it conflicts with your root composer.json require (10.2.x-dev).
    - drupal/commerce[2.1.0, ..., 2.4.0] require drupal/core ~8.4 -> found drupal/core[8.4.0-alpha1, ..., 8.9.x-dev] but it conflicts with your root composer.json require (10.2.x-dev).
    - drupal/commerce[2.5.0, ..., 2.9.0] require drupal/core ~8.5 -> found drupal/core[8.5.0-alpha1, ..., 8.9.x-dev] but it conflicts with your root composer.json require (10.2.x-dev).
    - drupal/commerce[2.10.0, ..., 2.14.0] require drupal/core ^8.6 -> found drupal/core[8.6.0-alpha1, ..., 8.9.x-dev] but it conflicts with your root composer.json require (10.2.x-dev).
    - drupal/commerce[2.15.0, ..., 2.16.0] require drupal/core ^8.7 -> found drupal/core[8.7.0-alpha1, ..., 8.9.x-dev] but it conflicts with your root composer.json require (10.2.x-dev).
    - drupal/commerce[2.17.0, ..., 2.18.0] require drupal/core ^8.7.7 || ^9 -> found drupal/core[8.7.7, ..., 8.9.x-dev, 9.0.0-alpha1, ..., 9.5.x-dev] but it conflicts with your root composer.json require (10.2.x-dev).
    - drupal/commerce[2.19.0, ..., 2.24.0] require drupal/core ^8.8 || ^9 -> found drupal/core[8.8.0-alpha1, ..., 8.9.x-dev, 9.0.0-alpha1, ..., 9.5.x-dev] but it conflicts with your root composer.json require (10.2.x-dev).
    - drupal/commerce[2.25.0, ..., 2.28.0] require drupal/core ^8.9 || ^9 -> found drupal/core[8.9.0-beta1, ..., 8.9.x-dev, 9.0.0-alpha1, ..., 9.5.x-dev] but it conflicts with your root composer.json require (10.2.x-dev).
    - drupal/commerce[2.29.0, ..., 2.x-dev] require ext-bcmath * -> it is missing from your system. Install or enable PHP's bcmath extension.
    - drupal/eca_commerce 1.0.0 requires drupal/commerce ^2 -> satisfiable by drupal/commerce[2.0.0-alpha1, ..., 2.x-dev].
    - Root composer.json requires drupal/eca_commerce 1.0.0 -> satisfiable by drupal/eca_commerce[1.0.0].

To enable extensions, verify that they are enabled in your .ini files:
    - /usr/local/etc/php/conf.d/docker-php-ext-gd.ini
    - /usr/local/etc/php/conf.d/docker-php-ext-imagick.ini
    - /usr/local/etc/php/conf.d/docker-php-ext-mcrypt.ini
    - /usr/local/etc/php/conf.d/docker-php-ext-opcache.ini
    - /usr/local/etc/php/conf.d/docker-php-ext-pdo_mysql.ini
    - /usr/local/etc/php/conf.d/docker-php-ext-sodium.ini
    - /usr/local/etc/php/conf.d/tugboat.ini
You can also run `php --ini` in a terminal to see which files are used by PHP in CLI mode.
Alternatively, you can run Composer with `--ignore-platform-req=ext-bcmath` to temporarily ignore these required extensions.

Use the option --with-all-dependencies (-W) to allow upgrades, downgrades and removals for packages currently locked to specific versions.

@mglaman thanks for the MR.

I'm marking this as Unassigned because I see an MR is open for review.